diff --git a/tests/oneway.thrift b/tests/oneway.thrift
new file mode 100644
index 0000000..835f53c
--- /dev/null
+++ b/tests/oneway.thrift
@@ -0,0 +1,3 @@
+service echo {
+    oneway void Test(1: string req)
+}
diff --git a/tests/test_oneway.py b/tests/test_oneway.py
new file mode 100644
index 0000000..812cfda
--- /dev/null
+++ b/tests/test_oneway.py
@@ -0,0 +1,32 @@
+import multiprocessing
+import thriftpy2
+import time
+from thriftpy2.rpc import make_client, make_server
+
+
+class Dispatcher(object):
+    def Test(self, req):
+        print("Get req msg: %s" % req)
+
+        assert req == "Hello!"
+
+
+class TestOneway(object):
+
+    oneway_thrift = thriftpy2.load("oneway.thrift")
+
+    def setup_class(self):
+        ctx = multiprocessing.get_context("fork")
+        server = make_server(self.oneway_thrift.echo, Dispatcher(), '127.0.0.1', 6000)
+        self.p = ctx.Process(target=server.serve)
+        self.p.start()
+        time.sleep(1)  # Wait a second for server to start.
+
+    def teardown_class(self):
+        self.p.terminate()
+
+    def test_echo(self):
+        req = "Hello!"
+        client = make_client(self.oneway_thrift.echo, '127.0.0.1', 6000)
+
+        assert client.Test(req) == None
diff --git a/thriftpy2/contrib/aio/client.py b/thriftpy2/contrib/aio/client.py
index 525e8d3..2e2136d 100644
--- a/thriftpy2/contrib/aio/client.py
+++ b/thriftpy2/contrib/aio/client.py
@@ -40,7 +40,9 @@ async def _req(self, _api, *args, **kwargs):
             return await self._recv(_api)
 
     async def _send(self, _api, **kwargs):
-        self._oprot.write_message_begin(_api, TMessageType.CALL, self._seqid)
+        oneway = getattr(getattr(self._service, _api + "_result"), "oneway")
+        msg_type = TMessageType.ONEWAY if oneway else TMessageType.CALL
+        self._oprot.write_message_begin(_api, msg_type, self._seqid)
         args = getattr(self._service, _api + "_args")()
         for k, v in kwargs.items():
             setattr(args, k, v)
diff --git a/thriftpy2/thrift.py b/thriftpy2/thrift.py
index 0c4322b..30cc517 100644
--- a/thriftpy2/thrift.py
+++ b/thriftpy2/thrift.py
@@ -219,7 +219,9 @@ def _req(self, _api, *args, **kwargs):
             return self._recv(_api)
 
     def _send(self, _api, **kwargs):
-        self._oprot.write_message_begin(_api, TMessageType.CALL, self._seqid)
+        oneway = getattr(getattr(self._service, _api + "_result"), "oneway")
+        msg_type = TMessageType.ONEWAY if oneway else TMessageType.CALL
+        self._oprot.write_message_begin(_api, msg_type, self._seqid)
         args = getattr(self._service, _api + "_args")()
         for k, v in kwargs.items():
             setattr(args, k, v)