diff --git a/src/wolfssl/__init__.py b/src/wolfssl/__init__.py
index 5f8ab83..f122d74 100644
--- a/src/wolfssl/__init__.py
+++ b/src/wolfssl/__init__.py
@@ -114,6 +114,17 @@ class WolfSSLX509(object):
 
         return san
 
+    def get_der(self):
+        outSz = _ffi.new("int *")
+        derPtr = _lib.wolfSSL_X509_get_der(self.native_object, outSz)
+
+        if derPtr == _ffi.NULL:
+            return None
+
+        derBytes = _ffi.buffer(derPtr, outSz[0])
+
+        return derBytes
+
 
 class SSLContext(object):
     """
diff --git a/src/wolfssl/_build_ffi.py b/src/wolfssl/_build_ffi.py
index 0bc15eb..a948968 100644
--- a/src/wolfssl/_build_ffi.py
+++ b/src/wolfssl/_build_ffi.py
@@ -108,6 +108,7 @@ ffi.cdef(
      */
     char* wolfSSL_X509_get_subjectCN(void*);
     char* wolfSSL_X509_get_next_altname(void*);
+    const unsigned char* wolfSSL_X509_get_der(void*, int*);
     """
 )