diff --git a/index.js b/index.js
index bdfeb70..fcd018a 100644
--- a/index.js
+++ b/index.js
@@ -123,6 +123,13 @@ const {
   encryptIDAES256CCM, decryptIDAES256CCM,
   encryptIDAES256GCM, decryptIDAES256GCM
 } = require("./lib/id/index");
+const {
+  encryptSEED, decryptSEED,
+  encryptSEEDCBC, decryptSEEDCBC,
+  encryptSEEDCFB, decryptSEEDCFB,
+  encryptSEEDECB, decryptSEEDECB,
+  encryptSEEDOFB, decryptSEEDOFB
+} = require("./lib/seed/index");
 const {
   encryptSM4, decryptSM4,
   encryptSM4CBC, decryptSM4CBC,
@@ -259,6 +266,11 @@ module.exports = {
   encryptIDAES192GCM, decryptIDAES192GCM,
   encryptIDAES256CCM, decryptIDAES256CCM,
   encryptIDAES256GCM, decryptIDAES256GCM,
+  encryptSEED, decryptSEED,
+  encryptSEEDCBC, decryptSEEDCBC,
+  encryptSEEDCFB, decryptSEEDCFB,
+  encryptSEEDECB, decryptSEEDECB,
+  encryptSEEDOFB, decryptSEEDOFB,
   encryptSM4, decryptSM4,
   encryptSM4CBC, decryptSM4CBC,
   encryptSM4CFB, decryptSM4CFB,
diff --git a/lib/algorithmList.js b/lib/algorithmList.js
index 9055b7c..8fbcbb9 100644
--- a/lib/algorithmList.js
+++ b/lib/algorithmList.js
@@ -114,6 +114,11 @@ const algorithmSupported = [
   "id-aes192-gcm",
   "id-aes256-ccm",
   "id-aes256-gcm",
+  "seed",
+  "seed-cbc",
+  "seed-cfb",
+  "seed-ecb",
+  "seed-ofb",
   "sm4",
   "sm4-cbc",
   "sm4-cfb",
@@ -174,12 +179,7 @@ const algorithmUnsupported = [
   "rc2-64",
   "rc2-64-cbc",
   "rc4-cbc",
-  "rc4-40",
-  "seed",
-  "seed-cbc",
-  "seed-cfb",
-  "seed-ecb",
-  "seed-ofb"
+  "rc4-40"
 ];
 
 module.exports = {
diff --git a/lib/decrypt.js b/lib/decrypt.js
index 0c26697..4dd8bdf 100644
--- a/lib/decrypt.js
+++ b/lib/decrypt.js
@@ -127,6 +127,13 @@ const {
   decryptIDAES256CCM,
   decryptIDAES256GCM
 } = require("./id/index");
+const {
+  decryptSEED,
+  decryptSEEDCBC,
+  decryptSEEDCFB,
+  decryptSEEDECB,
+  decryptSEEDOFB
+} = require("./seed/index");
 const {
   decryptSM4,
   decryptSM4CBC,
@@ -470,6 +477,21 @@ function decrypt(algorithm, data, password, extra = null) {
     return decryptIDAES256GCM(data, password, extra);
   }
 
+  /*****************************************************
+   *                      SEED                         *
+   *****************************************************/
+  if (algorithm === "seed") {
+    return decryptSEED(data, password, extra);
+  } else if (algorithm === "seed-cbc") {
+    return decryptSEEDCBC(data, password, extra);
+  } else if (algorithm === "seed-cfb") {
+    return decryptSEEDCFB(data, password, extra);
+  } else if (algorithm === "seed-ecb") {
+    return decryptSEEDECB(data, password, extra);
+  } else if (algorithm === "seed-ofb") {
+    return decryptSEEDOFB(data, password, extra);
+  }
+
   /*****************************************************
    *                      SM4                          *
    *****************************************************/
diff --git a/lib/encrypt.js b/lib/encrypt.js
index f292881..582e404 100644
--- a/lib/encrypt.js
+++ b/lib/encrypt.js
@@ -127,6 +127,13 @@ const {
   encryptIDAES256CCM,
   encryptIDAES256GCM
 } = require("./id/index");
+const {
+  encryptSEED,
+  encryptSEEDCBC,
+  encryptSEEDCFB,
+  encryptSEEDECB,
+  encryptSEEDOFB
+} = require("./seed/index");
 const {
   encryptSM4,
   encryptSM4CBC,
@@ -470,6 +477,21 @@ function encrypt(algorithm, data, password, extra = null) {
     return encryptIDAES256GCM(data, password, extra);
   }
 
+  /*****************************************************
+   *                      SEED                         *
+   *****************************************************/
+  if (algorithm === "seed") {
+    return encryptSEED(data, password, extra);
+  } else if (algorithm === "seed-cbc") {
+    return encryptSEEDCBC(data, password, extra);
+  } else if (algorithm === "seed-cfb") {
+    return encryptSEEDCFB(data, password, extra);
+  } else if (algorithm === "seed-ecb") {
+    return encryptSEEDECB(data, password, extra);
+  } else if (algorithm === "seed-ofb") {
+    return encryptSEEDOFB(data, password, extra);
+  }
+
   /*****************************************************
    *                      SM4                          *
    *****************************************************/
diff --git a/lib/seed/index.js b/lib/seed/index.js
new file mode 100644
index 0000000..78bb082
--- /dev/null
+++ b/lib/seed/index.js
@@ -0,0 +1,13 @@
+const { encryptSEED, decryptSEED } = require("./seed");
+const { encryptSEEDCBC, decryptSEEDCBC } = require("./seed-cbc");
+const { encryptSEEDCFB, decryptSEEDCFB } = require("./seed-cfb");
+const { encryptSEEDECB, decryptSEEDECB } = require("./seed-ecb");
+const { encryptSEEDOFB, decryptSEEDOFB } = require("./seed-ofb");
+
+module.exports = {
+  encryptSEED, decryptSEED,
+  encryptSEEDCBC, decryptSEEDCBC,
+  encryptSEEDCFB, decryptSEEDCFB,
+  encryptSEEDECB, decryptSEEDECB,
+  encryptSEEDOFB, decryptSEEDOFB
+};
diff --git a/lib/seed/seed-cbc.js b/lib/seed/seed-cbc.js
new file mode 100644
index 0000000..1a11e82
--- /dev/null
+++ b/lib/seed/seed-cbc.js
@@ -0,0 +1,67 @@
+const crypto = require("crypto");
+const zlib = require("zlib");
+
+/**
+ * Encrypts data using the SEED-CBC algorithm.
+ *
+ * @param {string} data - The data to be encrypted.
+ * @param {string} password - The password used for key derivation.
+ * @param {string|null} extra - Additional options for encryption (e.g., 'base64', 'binary', 'hex', or 'zlib').
+ * @returns {Buffer|string} - The encrypted data.
+ */
+function encryptSEEDCBC(data, password, extra = null) {
+  const salt = crypto.randomBytes(8);
+  const iv = crypto.randomBytes(16);
+  const key = crypto.pbkdf2Sync(password, salt, 100000, 16, "sha256");
+  const cipher = crypto.createCipheriv("seed-cbc", key, iv);
+  var encrypted = Buffer.concat([Buffer.from("Salted__"), salt, iv, cipher.update(data, "utf-8"), cipher.final()]);
+  if (extra === "base64") {
+    var encrypted = encrypted.toString("base64");
+  } else if (extra === "binary") {
+    var encrypted = encrypted.toString("binary");
+  } else if (extra === "hex") {
+    var encrypted = encrypted.toString("hex");
+  } else if (extra === "zlib") {
+    var encrypted = zlib.deflateSync(encrypted);
+  }
+
+  return encrypted;
+}
+
+/**
+ * Decrypts data using the SEED-CBC algorithm.
+ *
+ * @param {Buffer|string} data - The data to be decrypted.
+ * @param {string} password - The password used for key derivation.
+ * @param {string|null} extra - Additional options for decryption (e.g., 'base64', 'binary', 'hex', or 'zlib').
+ * @returns {string} - The decrypted data.
+ */
+function decryptSEEDCBC(encryptedData, password, extra = null) {
+  var data = encryptedData;
+  if (extra === "base64") {
+    var data = Buffer.from(data, "base64");
+  } else if (extra === "binary") {
+    var data = Buffer.from(data, "binary");
+  } else if (extra === "hex") {
+    var data = Buffer.from(data, "hex");
+  } else if (extra === "zlib") {
+    var data = zlib.inflateSync(data);
+  }
+
+  if (! Buffer.isBuffer(data)) {
+    var buffString = data;
+    var hexValues = buffString.replace(/<Buffer|>/g, "").split(" ").filter(Boolean);
+    var bufferArray = hexValues.map(hex => parseInt(hex, 16));
+    var data = Buffer.from(bufferArray);
+  }
+
+  const salt = data.slice(8, 16);
+  const iv = data.slice(16, 32);
+  const key = crypto.pbkdf2Sync(password, salt, 100000, 16, "sha256");
+  const decipher = crypto.createDecipheriv("seed-cbc", key, iv);
+  const decrypted = Buffer.concat([decipher.update(data.slice(32)), decipher.final()]).toString("utf-8");
+
+  return decrypted;
+}
+
+module.exports = { encryptSEEDCBC, decryptSEEDCBC };
diff --git a/lib/seed/seed-cfb.js b/lib/seed/seed-cfb.js
new file mode 100644
index 0000000..ec4049c
--- /dev/null
+++ b/lib/seed/seed-cfb.js
@@ -0,0 +1,67 @@
+const crypto = require("crypto");
+const zlib = require("zlib");
+
+/**
+ * Encrypts data using the SEED-CFB algorithm.
+ *
+ * @param {string} data - The data to be encrypted.
+ * @param {string} password - The password used for key derivation.
+ * @param {string|null} extra - Additional options for encryption (e.g., 'base64', 'binary', 'hex', or 'zlib').
+ * @returns {Buffer|string} - The encrypted data.
+ */
+function encryptSEEDCFB(data, password, extra = null) {
+  const salt = crypto.randomBytes(8);
+  const iv = crypto.randomBytes(16);
+  const key = crypto.pbkdf2Sync(password, salt, 100000, 16, "sha256");
+  const cipher = crypto.createCipheriv("seed-cfb", key, iv);
+  var encrypted = Buffer.concat([Buffer.from("Salted__"), salt, iv, cipher.update(data, "utf-8"), cipher.final()]);
+  if (extra === "base64") {
+    var encrypted = encrypted.toString("base64");
+  } else if (extra === "binary") {
+    var encrypted = encrypted.toString("binary");
+  } else if (extra === "hex") {
+    var encrypted = encrypted.toString("hex");
+  } else if (extra === "zlib") {
+    var encrypted = zlib.deflateSync(encrypted);
+  }
+
+  return encrypted;
+}
+
+/**
+ * Decrypts data using the SEED-CFB algorithm.
+ *
+ * @param {Buffer|string} data - The data to be decrypted.
+ * @param {string} password - The password used for key derivation.
+ * @param {string|null} extra - Additional options for decryption (e.g., 'base64', 'binary', 'hex', or 'zlib').
+ * @returns {string} - The decrypted data.
+ */
+function decryptSEEDCFB(encryptedData, password, extra = null) {
+  var data = encryptedData;
+  if (extra === "base64") {
+    var data = Buffer.from(data, "base64");
+  } else if (extra === "binary") {
+    var data = Buffer.from(data, "binary");
+  } else if (extra === "hex") {
+    var data = Buffer.from(data, "hex");
+  } else if (extra === "zlib") {
+    var data = zlib.inflateSync(data);
+  }
+
+  if (! Buffer.isBuffer(data)) {
+    var buffString = data;
+    var hexValues = buffString.replace(/<Buffer|>/g, "").split(" ").filter(Boolean);
+    var bufferArray = hexValues.map(hex => parseInt(hex, 16));
+    var data = Buffer.from(bufferArray);
+  }
+
+  const salt = data.slice(8, 16);
+  const iv = data.slice(16, 32);
+  const key = crypto.pbkdf2Sync(password, salt, 100000, 16, "sha256");
+  const decipher = crypto.createDecipheriv("seed-cfb", key, iv);
+  const decrypted = Buffer.concat([decipher.update(data.slice(32)), decipher.final()]).toString("utf-8");
+
+  return decrypted;
+}
+
+module.exports = { encryptSEEDCFB, decryptSEEDCFB };
diff --git a/lib/seed/seed-ecb.js b/lib/seed/seed-ecb.js
new file mode 100644
index 0000000..d03de29
--- /dev/null
+++ b/lib/seed/seed-ecb.js
@@ -0,0 +1,65 @@
+const crypto = require("crypto");
+const zlib = require("zlib");
+
+/**
+ * Encrypts data using the SEED-ECB algorithm.
+ *
+ * @param {string} data - The data to be encrypted.
+ * @param {string} password - The password used for key derivation.
+ * @param {string|null} extra - Additional options for encryption (e.g., 'base64', 'binary', 'hex', or 'zlib').
+ * @returns {Buffer|string} - The encrypted data.
+ */
+function encryptSEEDECB(data, password, extra = null) {
+  const salt = crypto.randomBytes(8);
+  const key = crypto.pbkdf2Sync(password, salt, 100000, 16, "sha256");
+  const cipher = crypto.createCipheriv("seed-ecb", key, null);
+  var encrypted = Buffer.concat([Buffer.from("Salted__"), salt, cipher.update(data, "utf-8"), cipher.final()]);
+  if (extra === "base64") {
+    var encrypted = encrypted.toString("base64");
+  } else if (extra === "binary") {
+    var encrypted = encrypted.toString("binary");
+  } else if (extra === "hex") {
+    var encrypted = encrypted.toString("hex");
+  } else if (extra === "zlib") {
+    var encrypted = zlib.deflateSync(encrypted);
+  }
+
+  return encrypted;
+}
+
+/**
+ * Decrypts data using the SEED-ECB algorithm.
+ *
+ * @param {Buffer|string} data - The data to be decrypted.
+ * @param {string} password - The password used for key derivation.
+ * @param {string|null} extra - Additional options for decryption (e.g., 'base64', 'binary', 'hex', or 'zlib').
+ * @returns {string} - The decrypted data.
+ */
+function decryptSEEDECB(encryptedData, password, extra = null) {
+  var data = encryptedData;
+  if (extra === "base64") {
+    var data = Buffer.from(data, "base64");
+  } else if (extra === "binary") {
+    var data = Buffer.from(data, "binary");
+  } else if (extra === "hex") {
+    var data = Buffer.from(data, "hex");
+  } else if (extra === "zlib") {
+    var data = zlib.inflateSync(data);
+  }
+
+  if (! Buffer.isBuffer(data)) {
+    var buffString = data;
+    var hexValues = buffString.replace(/<Buffer|>/g, "").split(" ").filter(Boolean);
+    var bufferArray = hexValues.map(hex => parseInt(hex, 16));
+    var data = Buffer.from(bufferArray);
+  }
+
+  const salt = data.slice(8, 16);
+  const key = crypto.pbkdf2Sync(password, salt, 100000, 16, "sha256");
+  const decipher = crypto.createDecipheriv("seed-ecb", key, null);
+  const decrypted = Buffer.concat([decipher.update(data.slice(16)), decipher.final()]).toString("utf-8");
+
+  return decrypted;
+}
+
+module.exports = { encryptSEEDECB, decryptSEEDECB };
diff --git a/lib/seed/seed-ofb.js b/lib/seed/seed-ofb.js
new file mode 100644
index 0000000..7079447
--- /dev/null
+++ b/lib/seed/seed-ofb.js
@@ -0,0 +1,67 @@
+const crypto = require("crypto");
+const zlib = require("zlib");
+
+/**
+ * Encrypts data using the SEED-OFB algorithm.
+ *
+ * @param {string} data - The data to be encrypted.
+ * @param {string} password - The password used for key derivation.
+ * @param {string|null} extra - Additional options for encryption (e.g., 'base64', 'binary', 'hex', or 'zlib').
+ * @returns {Buffer|string} - The encrypted data.
+ */
+function encryptSEEDOFB(data, password, extra = null) {
+  const salt = crypto.randomBytes(8);
+  const iv = crypto.randomBytes(16);
+  const key = crypto.pbkdf2Sync(password, salt, 100000, 16, "sha256");
+  const cipher = crypto.createCipheriv("seed-ofb", key, iv);
+  var encrypted = Buffer.concat([Buffer.from("Salted__"), salt, iv, cipher.update(data, "utf-8"), cipher.final()]);
+  if (extra === "base64") {
+    var encrypted = encrypted.toString("base64");
+  } else if (extra === "binary") {
+    var encrypted = encrypted.toString("binary");
+  } else if (extra === "hex") {
+    var encrypted = encrypted.toString("hex");
+  } else if (extra === "zlib") {
+    var encrypted = zlib.deflateSync(encrypted);
+  }
+
+  return encrypted;
+}
+
+/**
+ * Decrypts data using the SEED-OFB algorithm.
+ *
+ * @param {Buffer|string} data - The data to be decrypted.
+ * @param {string} password - The password used for key derivation.
+ * @param {string|null} extra - Additional options for decryption (e.g., 'base64', 'binary', 'hex', or 'zlib').
+ * @returns {string} - The decrypted data.
+ */
+function decryptSEEDOFB(encryptedData, password, extra = null) {
+  var data = encryptedData;
+  if (extra === "base64") {
+    var data = Buffer.from(data, "base64");
+  } else if (extra === "binary") {
+    var data = Buffer.from(data, "binary");
+  } else if (extra === "hex") {
+    var data = Buffer.from(data, "hex");
+  } else if (extra === "zlib") {
+    var data = zlib.inflateSync(data);
+  }
+
+  if (! Buffer.isBuffer(data)) {
+    var buffString = data;
+    var hexValues = buffString.replace(/<Buffer|>/g, "").split(" ").filter(Boolean);
+    var bufferArray = hexValues.map(hex => parseInt(hex, 16));
+    var data = Buffer.from(bufferArray);
+  }
+
+  const salt = data.slice(8, 16);
+  const iv = data.slice(16, 32);
+  const key = crypto.pbkdf2Sync(password, salt, 100000, 16, "sha256");
+  const decipher = crypto.createDecipheriv("seed-ofb", key, iv);
+  const decrypted = Buffer.concat([decipher.update(data.slice(32)), decipher.final()]).toString("utf-8");
+
+  return decrypted;
+}
+
+module.exports = { encryptSEEDOFB, decryptSEEDOFB };
diff --git a/lib/seed/seed.js b/lib/seed/seed.js
new file mode 100644
index 0000000..4b1cd4a
--- /dev/null
+++ b/lib/seed/seed.js
@@ -0,0 +1,67 @@
+const crypto = require("crypto");
+const zlib = require("zlib");
+
+/**
+ * Encrypts data using the SEED algorithm.
+ *
+ * @param {string} data - The data to be encrypted.
+ * @param {string} password - The password used for key derivation.
+ * @param {string|null} extra - Additional options for encryption (e.g., 'base64', 'binary', 'hex', or 'zlib').
+ * @returns {Buffer|string} - The encrypted data.
+ */
+function encryptSEED(data, password, extra = null) {
+  const salt = crypto.randomBytes(8);
+  const iv = crypto.randomBytes(16);
+  const key = crypto.pbkdf2Sync(password, salt, 100000, 16, "sha256");
+  const cipher = crypto.createCipheriv("seed", key, iv);
+  var encrypted = Buffer.concat([Buffer.from("Salted__"), salt, iv, cipher.update(data, "utf-8"), cipher.final()]);
+  if (extra === "base64") {
+    var encrypted = encrypted.toString("base64");
+  } else if (extra === "binary") {
+    var encrypted = encrypted.toString("binary");
+  } else if (extra === "hex") {
+    var encrypted = encrypted.toString("hex");
+  } else if (extra === "zlib") {
+    var encrypted = zlib.deflateSync(encrypted);
+  }
+
+  return encrypted;
+}
+
+/**
+ * Decrypts data using the SEED algorithm.
+ *
+ * @param {Buffer|string} data - The data to be decrypted.
+ * @param {string} password - The password used for key derivation.
+ * @param {string|null} extra - Additional options for decryption (e.g., 'base64', 'binary', 'hex', or 'zlib').
+ * @returns {string} - The decrypted data.
+ */
+function decryptSEED(encryptedData, password, extra = null) {
+  var data = encryptedData;
+  if (extra === "base64") {
+    var data = Buffer.from(data, "base64");
+  } else if (extra === "binary") {
+    var data = Buffer.from(data, "binary");
+  } else if (extra === "hex") {
+    var data = Buffer.from(data, "hex");
+  } else if (extra === "zlib") {
+    var data = zlib.inflateSync(data);
+  }
+
+  if (! Buffer.isBuffer(data)) {
+    var buffString = data;
+    var hexValues = buffString.replace(/<Buffer|>/g, "").split(" ").filter(Boolean);
+    var bufferArray = hexValues.map(hex => parseInt(hex, 16));
+    var data = Buffer.from(bufferArray);
+  }
+
+  const salt = data.slice(8, 16);
+  const iv = data.slice(16, 32);
+  const key = crypto.pbkdf2Sync(password, salt, 100000, 16, "sha256");
+  const decipher = crypto.createDecipheriv("seed", key, iv);
+  const decrypted = Buffer.concat([decipher.update(data.slice(32)), decipher.final()]).toString("utf-8");
+
+  return decrypted;
+}
+
+module.exports = { encryptSEED, decryptSEED };