diff --git a/types/secp256k1/index.d.ts b/types/secp256k1/index.d.ts
new file mode 100644
index 0000000000..686171565b
--- /dev/null
+++ b/types/secp256k1/index.d.ts
@@ -0,0 +1,144 @@
+// Type definitions for secp256k1 3.5
+// Project: https://github.com/cryptocoinjs/secp256k1-node
+// Definitions by: Anler <https://github.com/anler>
+// Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
+
+/// <reference types="node" />
+
+/** Options for the `sign` function */
+export interface SignOptions {
+    /** Nonce generator. By default it is rfc6979 */
+    noncefn?: (message: Buffer, privateKey: Buffer, algo: Buffer | null,
+               data: Buffer | null, attempt: number) => Buffer;
+
+    /**
+     * Additional data for noncefn (RFC 6979 3.6) (32 bytes).
+     *
+     * By default is `null`.
+     */
+    data?: Buffer;
+}
+
+/**
+ * Verify an ECDSA privateKey.
+ */
+export function privateKeyVerify(privateKey: Buffer): boolean;
+
+/**
+ * Export a privateKey in DER format.
+ */
+export function privateKeyExport(privateKey: Buffer, compressed?: boolean): Buffer;
+
+/**
+ * Import a privateKey in DER format.
+ */
+export function privateKeyImport(privateKey: Buffer): Buffer;
+
+/**
+ * Negate a privateKey by subtracting it from the order of the curve's base point.
+ */
+export function privateKeyNegate(privateKey: Buffer): Buffer;
+
+/**
+ * Compute the inverse of a privateKey (modulo the order of the curve's base point).
+ */
+export function privateKeyModInverse(privateKey: Buffer): Buffer;
+
+/**
+ * Tweak a privateKey by adding tweak to it.
+ */
+export function privateKeyTweakAdd(privateKey: Buffer, tweak: Buffer): Buffer;
+
+/**
+ * Tweak a privateKey by multiplying it by a tweak.
+ */
+export function privateKeyTweakMul(privateKey: Buffer, tweak: Buffer): Buffer;
+
+/**
+ * Compute the public key for a privateKey.
+ */
+export function publicKeyCreate(privateKey: Buffer, compressed?: boolean): Buffer;
+
+/**
+ * Convert a publicKey to compressed or uncompressed form.
+ */
+export function publicKeyConvert(publicKey: Buffer, compressed?: boolean): Buffer;
+
+/**
+ * Verify an ECDSA publicKey.
+ */
+export function publicKeyVerify(publicKey: Buffer): boolean;
+
+/**
+ * Tweak a publicKey by adding tweak times the generator to it.
+ */
+export function publicKeyTweakAdd(publicKey: Buffer, tweak: Buffer, compressed?: boolean): Buffer;
+
+/**
+ * Tweak a publicKey by multiplying it by a tweak value.
+ */
+export function publicKeyTweakMul(publicKey: Buffer, tweak: Buffer, compressed?: boolean): Buffer;
+
+/**
+ * Add a given publicKeys together.
+ */
+export function publicKeyCombine(publicKeys: Buffer[], compressed?: boolean): Buffer;
+
+/**
+ * Convert a signature to a normalized lower-S form.
+ */
+export function signatureNormalize(signature: Buffer): Buffer;
+
+/**
+ * Serialize an ECDSA signature in DER format.
+ */
+export function signatureExport(signature: Buffer): Buffer;
+
+/**
+ * Parse a DER ECDSA signature (follow by BIP66).
+ */
+export function signatureImport(signature: Buffer): Buffer;
+
+/**
+ * Same as `signatureImport` but not follow by BIP66.
+ */
+export function signatureImportLax(signature: Buffer): Buffer;
+
+/**
+ * Create an ECDSA signature. Always return low-S signature.
+ *
+ * Inputs: 32-byte message `m`, 32-byte scalar key `d`, 32-byte scalar nonce `k`.
+ * - Compute point `R = k * G`. Reject nonce if R's `x` coordinate is zero.
+ * - Compute 32-byte scalar `r`, the serialization of R's `x` coordinate.
+ * - Compose 32-byte scalar `s = k^-1 * (r * d + m)`. Reject nonce if `s` is zero.
+ * - The signature is `(r, s)`.
+ */
+export function sign(message: Buffer, privateKey: Buffer, options?: SignOptions): {signature: Buffer, recovery: number};
+
+/**
+ * Verify an ECDSA signature.
+ *
+ * Note: return false for high signatures!
+ *
+ * Inputs: 32-byte message `m`, public key point `Q`, signature: (32-byte `r`, scalar `s`).
+ * - Signature is invalid if `r` is zero.
+ * - Signature is invalid if `s` is zero.
+ * - Compute point `R = (s^-1 * m * G + s^-1 * r * Q)`. Reject if `R` is infinity.
+ * - Signature is valid if R's `x` coordinate equals to `r`.
+ */
+export function verify(message: Buffer, signature: Buffer, publicKey: Buffer): boolean;
+
+/**
+ * Recover an ECDSA public key from a signature.
+ */
+export function recover(message: Buffer, signature: Buffer, recovery: number, compressed?: boolean): Buffer;
+
+/**
+ * Compute an EC Diffie-Hellman secret and applied sha256 to compressed public key.
+ */
+export function ecdh(publicKey: Buffer, privateKey: Buffer): Buffer;
+
+/**
+ * Compute an EC Diffie-Hellman secret and return public key as result.
+ */
+export function ecdhUnsafe(publicKey: Buffer, privateKey: Buffer, compressed?: boolean): Buffer;
diff --git a/types/secp256k1/secp256k1-tests.ts b/types/secp256k1/secp256k1-tests.ts
new file mode 100644
index 0000000000..03754354b1
--- /dev/null
+++ b/types/secp256k1/secp256k1-tests.ts
@@ -0,0 +1,11 @@
+import { SignOptions, sign } from "secp256k1";
+
+const opts: SignOptions = {
+    data: Buffer.from([0x62, 0x75, 0x66, 0x66, 0x65, 0x72])
+};
+
+const message = Buffer.from([0x62, 0x75, 0x66, 0x66, 0x65, 0x72]);
+
+const prvKey = Buffer.from([0x62, 0x75, 0x66, 0x66, 0x65, 0x72]);
+
+sign(message, prvKey, opts);
diff --git a/types/secp256k1/tsconfig.json b/types/secp256k1/tsconfig.json
new file mode 100644
index 0000000000..8d15f80548
--- /dev/null
+++ b/types/secp256k1/tsconfig.json
@@ -0,0 +1,23 @@
+{
+    "compilerOptions": {
+        "module": "commonjs",
+        "lib": [
+            "es6"
+        ],
+        "noImplicitAny": true,
+        "noImplicitThis": true,
+        "strictNullChecks": true,
+        "strictFunctionTypes": true,
+        "baseUrl": "../",
+        "typeRoots": [
+            "../"
+        ],
+        "types": [],
+        "noEmit": true,
+        "forceConsistentCasingInFileNames": true
+    },
+    "files": [
+        "index.d.ts",
+        "secp256k1-tests.ts"
+    ]
+}
diff --git a/types/secp256k1/tslint.json b/types/secp256k1/tslint.json
new file mode 100644
index 0000000000..3db14f85ea
--- /dev/null
+++ b/types/secp256k1/tslint.json
@@ -0,0 +1 @@
+{ "extends": "dtslint/dt.json" }