diff --git a/python/paddle/fluid/__init__.py b/python/paddle/fluid/__init__.py
index 04f6905ce68d96556c4e037791d6e9fb80c03f37..1e6482e3c18a6fe8289ca301c684cb9834cacb21 100644
--- a/python/paddle/fluid/__init__.py
+++ b/python/paddle/fluid/__init__.py
@@ -20,6 +20,16 @@ from framework import *
 import executor
 from executor import *
 
+import trainer
+from trainer import Trainer
+from trainer import Event
+
+import inferencer
+from inferencer import Inferencer
+
+import params
+from params import Params
+
 import io
 import evaluator
 import initializer
@@ -47,7 +57,8 @@ from parallel_executor import ParallelExecutor
 
 Tensor = LoDTensor
 
-__all__ = framework.__all__ + executor.__all__ + concurrency.__all__ + [
+__all__ = framework.__all__ + executor.__all__ + concurrency.__all__ +\
+          trainer.__all__ + inferencer.__all__ + params.__all__ + [
     'io',
     'initializer',
     'layers',
diff --git a/python/paddle/fluid/inferencer.py b/python/paddle/fluid/inferencer.py
new file mode 100644
index 0000000000000000000000000000000000000000..3ea50bf196d00152e6579623c981ecbfb57b8e3b
--- /dev/null
+++ b/python/paddle/fluid/inferencer.py
@@ -0,0 +1,31 @@
+#   Copyright (c) 2018 PaddlePaddle Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+__all__ = ['Inferencer', ]
+
+
+class Inferencer(object):
+    def __init__(self, network_func, params, place=None):
+        # 1. we need to generate a framework.Program by calling
+        # network_func. Reference: fluid.program_guard in test_word2vec.py
+
+        # 2. move the default_main_program to self.program.
+
+        # 3. run the default_startup program.
+        self.params = params
+        self.place = place
+
+    def infer(self, inputs):
+        # run self.program
+        pass
diff --git a/python/paddle/fluid/params.py b/python/paddle/fluid/params.py
new file mode 100644
index 0000000000000000000000000000000000000000..a5d257e53a2958acd1b8f6ef29d0f9f531b36678
--- /dev/null
+++ b/python/paddle/fluid/params.py
@@ -0,0 +1,39 @@
+#   Copyright (c) 2018 PaddlePaddle Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from . import core
+
+__all__ = ['Params', ]
+
+
+class Params(object):
+    def __init__(self, path=None):
+        self.scope = core.Scope()
+
+        if path:
+            self._load(path)
+
+    def _load(self, path):
+        # reference: load_persistables in io.py
+        pass
+
+    def save(self, path):
+        # reference: save_persistables in io.py
+        pass
+
+    def add_params(self, scope):
+        # take the keys from the scope,
+        # if not already exists in self.scope,
+        # add the key and value into self.scope.
+        pass
diff --git a/python/paddle/fluid/trainer.py b/python/paddle/fluid/trainer.py
new file mode 100644
index 0000000000000000000000000000000000000000..aeda67650205a473486b05fdd5b4364753fb18ca
--- /dev/null
+++ b/python/paddle/fluid/trainer.py
@@ -0,0 +1,55 @@
+#   Copyright (c) 2018 PaddlePaddle Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+__all__ = [
+    'Event',
+    'Trainer',
+]
+
+
+class Event(object):
+    BEGIN_EPOCH = 0
+    END_EPOCH = 1
+    BEGIN_STEP = 2
+    END_STEP = 3
+
+    def __init__(self):
+        self.step = 0
+        self.epoch = 0
+        self.type = Event.BEGIN_EPOCH
+
+
+class Trainer(object):
+    def __init__(self, network_func, optimizer, params=None, place=None):
+        # 1. we need to generate a framework.Program by calling
+        # network_func. Reference: fluid.program_guard in
+        # test_word2vec.py
+
+        # 2. move the default_main_program to self.program and run the
+        # default_startup program on an empty core.Scope()
+
+        # 3. call self.params.add_vars with the initialized scope, it
+        # will add the new vars of the initialized scope into
+        # self.params.
+        self.network_func = network_func
+        self.optimizer = optimizer
+        self.params = params
+        self.place = place
+        # TODO(helin): support distributed training
+
+    def train(self, reader, num_epochs, event_handler):
+        pass
+
+    def test(self, reader):
+        pass