diff --git a/base/message_loop/message_loop.cc b/base/message_loop/message_loop.cc
index e14ce85..229eae7 100644
--- a/base/message_loop/message_loop.cc
+++ b/base/message_loop/message_loop.cc
@@ -125,7 +125,7 @@
       run_loop_(NULL) {
   Init();
 
-  pump_.reset(CreateMessagePumpForType(type));
+  pump_ = CreateMessagePumpForType(type).Pass();
 }
 
 MessageLoop::MessageLoop(scoped_ptr<MessagePump> pump)
@@ -201,27 +201,27 @@
 }
 
 // static
-MessagePump* MessageLoop::CreateMessagePumpForType(Type type) {
+scoped_ptr<MessagePump> MessageLoop::CreateMessagePumpForType(Type type) {
 // TODO(rvargas): Get rid of the OS guards.
 #if defined(OS_WIN)
-#define MESSAGE_PUMP_UI new MessagePumpForUI()
-#define MESSAGE_PUMP_IO new MessagePumpForIO()
+#define MESSAGE_PUMP_UI scoped_ptr<MessagePump>(new MessagePumpForUI())
+#define MESSAGE_PUMP_IO scoped_ptr<MessagePump>(new MessagePumpForIO())
 #elif defined(OS_IOS)
-#define MESSAGE_PUMP_UI MessagePumpMac::Create()
-#define MESSAGE_PUMP_IO new MessagePumpIOSForIO()
+#define MESSAGE_PUMP_UI scoped_ptr<MessagePump>(MessagePumpMac::Create())
+#define MESSAGE_PUMP_IO scoped_ptr<MessagePump>(new MessagePumpIOSForIO())
 #elif defined(OS_MACOSX)
-#define MESSAGE_PUMP_UI MessagePumpMac::Create()
-#define MESSAGE_PUMP_IO new MessagePumpLibevent()
+#define MESSAGE_PUMP_UI scoped_ptr<MessagePump>(MessagePumpMac::Create())
+#define MESSAGE_PUMP_IO scoped_ptr<MessagePump>(new MessagePumpLibevent())
 #elif defined(OS_NACL)
 // Currently NaCl doesn't have a UI MessageLoop.
 // TODO(abarth): Figure out if we need this.
-#define MESSAGE_PUMP_UI NULL
+#define MESSAGE_PUMP_UI scoped_ptr<MessagePump>()
 // ipc_channel_nacl.cc uses a worker thread to do socket reads currently, and
 // doesn't require extra support for watching file descriptors.
-#define MESSAGE_PUMP_IO new MessagePumpDefault()
+#define MESSAGE_PUMP_IO scoped_ptr<MessagePump>(new MessagePumpDefault())
 #elif defined(OS_POSIX)  // POSIX but not MACOSX.
-#define MESSAGE_PUMP_UI new MessagePumpForUI()
-#define MESSAGE_PUMP_IO new MessagePumpLibevent()
+#define MESSAGE_PUMP_UI scoped_ptr<MessagePump>(new MessagePumpForUI())
+#define MESSAGE_PUMP_IO scoped_ptr<MessagePump>(new MessagePumpLibevent())
 #else
 #error Not implemented
 #endif
@@ -235,14 +235,14 @@
     return MESSAGE_PUMP_IO;
 #if defined(TOOLKIT_GTK)
   if (type == MessageLoop::TYPE_GPU)
-    return new MessagePumpX11();
+    return scoped_ptr<MessagePump>(new MessagePumpX11());
 #endif
 #if defined(OS_ANDROID)
   if (type == MessageLoop::TYPE_JAVA)
     return MESSAGE_PUMP_UI;
 #endif
   DCHECK_EQ(MessageLoop::TYPE_DEFAULT, type);
-  return new MessagePumpDefault();
+  return scoped_ptr<MessagePump>(new MessagePumpDefault());
 }
 
 void MessageLoop::AddDestructionObserver(
diff --git a/base/message_loop/message_loop.h b/base/message_loop/message_loop.h
index 956f5f0..400a5ec 100644
--- a/base/message_loop/message_loop.h
+++ b/base/message_loop/message_loop.h
@@ -154,7 +154,7 @@
 
   static void EnableHistogrammer(bool enable_histogrammer);
 
-  typedef MessagePump* (MessagePumpFactory)();
+  typedef scoped_ptr<MessagePump> (MessagePumpFactory)();
   // Uses the given base::MessagePumpForUIFactory to override the default
   // MessagePump implementation for 'TYPE_UI'. Returns true if the factory
   // was successfully registered.
@@ -162,10 +162,7 @@
 
   // Creates the default MessagePump based on |type|. Caller owns return
   // value.
-  // TODO(sky): convert this and InitMessagePumpForUIFactory() to return a
-  // scoped_ptr.
-  static MessagePump* CreateMessagePumpForType(Type type);
-
+  static scoped_ptr<MessagePump> CreateMessagePumpForType(Type type);
   // A DestructionObserver is notified when the current MessageLoop is being
   // destroyed.  These observers are notified prior to MessageLoop::current()
   // being changed to return NULL.  This gives interested parties the chance to
diff --git a/base/message_loop/message_loop_unittest.cc b/base/message_loop/message_loop_unittest.cc
index 7921c9b..4637165 100644
--- a/base/message_loop/message_loop_unittest.cc
+++ b/base/message_loop/message_loop_unittest.cc
@@ -36,15 +36,15 @@
 
 namespace {
 
-MessagePump* TypeDefaultMessagePumpFactory() {
+scoped_ptr<MessagePump> TypeDefaultMessagePumpFactory() {
   return MessageLoop::CreateMessagePumpForType(MessageLoop::TYPE_DEFAULT);
 }
 
-MessagePump* TypeIOMessagePumpFactory() {
+scoped_ptr<MessagePump> TypeIOMessagePumpFactory() {
   return MessageLoop::CreateMessagePumpForType(MessageLoop::TYPE_IO);
 }
 
-MessagePump* TypeUIMessagePumpFactory() {
+scoped_ptr<MessagePump> TypeUIMessagePumpFactory() {
   return MessageLoop::CreateMessagePumpForType(MessageLoop::TYPE_UI);
 }
 
diff --git a/base/test/test_support_android.cc b/base/test/test_support_android.cc
index 1ad4c2b..b67ecac 100644
--- a/base/test/test_support_android.cc
+++ b/base/test/test_support_android.cc
@@ -133,8 +133,8 @@
   }
 };
 
-base::MessagePump* CreateMessagePumpForUIStub() {
-  return new MessagePumpForUIStub();
+scoped_ptr<base::MessagePump> CreateMessagePumpForUIStub() {
+  return scoped_ptr<base::MessagePump>(new MessagePumpForUIStub());
 };
 
 // Provides the test path for DIR_MODULE and DIR_ANDROID_APP_DATA.
diff --git a/mojo/common/message_pump_mojo_unittest.cc b/mojo/common/message_pump_mojo_unittest.cc
index 4276a0d..fb5ae24 100644
--- a/mojo/common/message_pump_mojo_unittest.cc
+++ b/mojo/common/message_pump_mojo_unittest.cc
@@ -11,8 +11,8 @@
 namespace common {
 namespace test {
 
-base::MessagePump* CreateMojoMessagePump() {
-  return new MessagePumpMojo();
+scoped_ptr<base::MessagePump> CreateMojoMessagePump() {
+  return scoped_ptr<base::MessagePump>(new MessagePumpMojo());
 }
 
 RUN_MESSAGE_LOOP_TESTS(Mojo, &CreateMojoMessagePump);