diff --git a/tests/st/func/datavisual/histogram/__init__.py b/tests/st/func/datavisual/histogram/__init__.py
new file mode 100644
index 0000000000000000000000000000000000000000..e30774307ca2107b3a81c071ad33c042ef924790
--- /dev/null
+++ b/tests/st/func/datavisual/histogram/__init__.py
@@ -0,0 +1,14 @@
+# Copyright 2020 Huawei Technologies Co., Ltd
+#
+# 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.
+# ============================================================================
diff --git a/tests/st/func/datavisual/histogram/test_histogram_restful_api.py b/tests/st/func/datavisual/histogram/test_histogram_restful_api.py
new file mode 100644
index 0000000000000000000000000000000000000000..f693d499a5082d202f7918972f94cc7018761add
--- /dev/null
+++ b/tests/st/func/datavisual/histogram/test_histogram_restful_api.py
@@ -0,0 +1,55 @@
+# Copyright 2020 Huawei Technologies Co., Ltd
+#
+# 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.
+# ============================================================================
+"""
+Function:
+    Test histograms restful api.
+Usage:
+    pytest tests/st/func/datavisual
+"""
+import pytest
+
+from mindinsight.datavisual.common.enums import PluginNameEnum
+
+from .....utils.tools import get_url
+from .. import globals as gbl
+
+BASE_URL = '/v1/mindinsight/datavisual/histograms'
+
+
+class TestHistograms:
+    """Test Histograms."""
+
+    @pytest.mark.level0
+    @pytest.mark.env_single
+    @pytest.mark.platform_x86_cpu
+    @pytest.mark.platform_arm_ascend_training
+    @pytest.mark.platform_x86_gpu_training
+    @pytest.mark.platform_x86_ascend_training
+    @pytest.mark.usefixtures("init_summary_logs")
+    def test_histograms(self, client):
+        """Test getting histogram data."""
+        plugin_name = PluginNameEnum.HISTOGRAM.value
+        train_id = gbl.get_train_ids()[0]
+        tag_name = gbl.get_tags(train_id, plugin_name)[0]
+        expected_histograms = gbl.get_metadata(train_id, tag_name)
+
+        params = dict(train_id=train_id, tag=tag_name)
+        url = get_url(BASE_URL, params)
+        response = client.get(url)
+        histograms = response.get_json().get("histograms")
+
+        for histograms, expected_histograms in zip(histograms, expected_histograms):
+            assert histograms.get("wall_time") == expected_histograms.get("wall_time")
+            assert histograms.get("step") == expected_histograms.get("step")
diff --git a/tests/ut/backend/datavisual/conftest.py b/tests/ut/backend/datavisual/conftest.py
index 431dc03e213efc5deae5a470fa1f014d5c9ea3a8..a75c248d5879eebe95e80ab4aa20d1c0870fddcf 100644
--- a/tests/ut/backend/datavisual/conftest.py
+++ b/tests/ut/backend/datavisual/conftest.py
@@ -54,5 +54,6 @@ TRAIN_ROUTES = dict(
     graph_single_node='/v1/mindinsight/datavisual/graphs/single-node',
     image_metadata='/v1/mindinsight/datavisual/image/metadata',
     image_single_image='/v1/mindinsight/datavisual/image/single-image',
-    scalar_metadata='/v1/mindinsight/datavisual/scalar/metadata'
+    scalar_metadata='/v1/mindinsight/datavisual/scalar/metadata',
+    histograms='/v1/mindinsight/datavisual/histograms'
 )
diff --git a/tests/ut/backend/datavisual/test_train_visual_api.py b/tests/ut/backend/datavisual/test_train_visual_api.py
index 831edbf34c2e5175ecad42ba6e8a4fd116628c16..08d56a25a5ce2a2b914e3390ce0ed7450af9e078 100644
--- a/tests/ut/backend/datavisual/test_train_visual_api.py
+++ b/tests/ut/backend/datavisual/test_train_visual_api.py
@@ -26,6 +26,7 @@ from mindinsight.datavisual.data_transform.graph import NodeTypeEnum
 from mindinsight.datavisual.processors.graph_processor import GraphProcessor
 from mindinsight.datavisual.processors.images_processor import ImageProcessor
 from mindinsight.datavisual.processors.scalars_processor import ScalarsProcessor
+from mindinsight.datavisual.processors.histogram_processor import HistogramProcessor
 
 from ....utils.tools import get_url
 from .conftest import TRAIN_ROUTES
@@ -432,3 +433,42 @@ class TestTrainVisual:
         assert response.status_code == 200
         results = response.get_json()
         assert results == test_name
+
+    def test_histograms_with_params_miss(self, client):
+        """Parsing missing params to get histogram data."""
+        params = dict()
+        url = get_url(TRAIN_ROUTES['histograms'], params)
+        response = client.get(url)
+        results = response.get_json()
+        assert response.status_code == 400
+        assert results['error_code'] == '50540003'
+        assert results['error_msg'] == "Param missing. 'train_id' is required."
+
+        train_id = "aa"
+        params = dict(train_id=train_id)
+        url = get_url(TRAIN_ROUTES['histograms'], params)
+        response = client.get(url)
+        results = response.get_json()
+        assert response.status_code == 400
+        assert results['error_code'] == '50540003'
+        assert results['error_msg'] == "Param missing. 'tag' is required."
+
+    @patch.object(HistogramProcessor, 'get_histograms')
+    def test_histograms_success(self, mock_histogram_processor, client):
+        """Parsing available params to get histogram data."""
+        test_train_id = "aa"
+        test_tag = "bb"
+        expect_resp = {
+            'histograms': [{'buckets': [[1, 2, 3]]}],
+            'train_id': test_train_id,
+            'tag': test_tag
+        }
+        get_histograms = Mock(return_value=expect_resp)
+        mock_histogram_processor.side_effect = get_histograms
+
+        params = dict(train_id=test_train_id, tag=test_tag)
+        url = get_url(TRAIN_ROUTES['histograms'], params)
+        response = client.get(url)
+        assert response.status_code == 200
+        results = response.get_json()
+        assert results == expect_resp
diff --git a/tests/ut/datavisual/processors/test_histogram_processor.py b/tests/ut/datavisual/processors/test_histogram_processor.py
new file mode 100644
index 0000000000000000000000000000000000000000..638d2115fe4c3a00fc4b2fe412c7869559cb1309
--- /dev/null
+++ b/tests/ut/datavisual/processors/test_histogram_processor.py
@@ -0,0 +1,117 @@
+# Copyright 2020 Huawei Technologies Co., Ltd
+#
+# 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.
+# ============================================================================
+"""
+Function:
+    Test histogram processor.
+Usage:
+    pytest tests/ut/datavisual
+"""
+import tempfile
+from unittest.mock import Mock
+
+import pytest
+
+from mindinsight.datavisual.common.enums import PluginNameEnum
+from mindinsight.datavisual.common.exceptions import TrainJobNotExistError
+from mindinsight.datavisual.common.exceptions import HistogramNotExistError
+from mindinsight.datavisual.data_transform import data_manager
+from mindinsight.datavisual.data_transform.loader_generators.data_loader_generator import DataLoaderGenerator
+from mindinsight.datavisual.processors.histogram_processor import HistogramProcessor
+from mindinsight.datavisual.utils import crc32
+
+from ....utils.log_operations import LogOperations
+from ....utils.tools import check_loading_done, delete_files_or_dirs
+from ..mock import MockLogger
+
+
+class TestHistogramProcessor:
+    """Test histogram processor api."""
+    _steps_list = [1, 3, 5]
+    _tag_name = 'tag_name'
+    _plugin_name = 'histogram'
+    _complete_tag_name = f'{_tag_name}/{_plugin_name}'
+
+    _temp_path = None
+    _histograms = None
+    _mock_data_manager = None
+    _train_id = None
+
+    _generated_path = []
+
+    @classmethod
+    def setup_class(cls):
+        """Mock common environment for histograms unittest."""
+        crc32.CheckValueAgainstData = Mock(return_value=True)
+        data_manager.logger = MockLogger
+
+    def teardown_class(self):
+        """Delete temp files."""
+        delete_files_or_dirs(self._generated_path)
+
+    @pytest.fixture(scope='function')
+    def load_histogram_record(self):
+        """Load histogram record."""
+        summary_base_dir = tempfile.mkdtemp()
+        log_dir = tempfile.mkdtemp(dir=summary_base_dir)
+        self._train_id = log_dir.replace(summary_base_dir, ".")
+
+        log_operation = LogOperations()
+        self._temp_path, self._histograms, _ = log_operation.generate_log(
+            PluginNameEnum.HISTOGRAM.value, log_dir, dict(step=self._steps_list, tag=self._tag_name))
+        self._generated_path.append(summary_base_dir)
+
+        self._mock_data_manager = data_manager.DataManager([DataLoaderGenerator(summary_base_dir)])
+        self._mock_data_manager.start_load_data(reload_interval=0)
+
+        # wait for loading done
+        check_loading_done(self._mock_data_manager, time_limit=5)
+
+    @pytest.mark.usefixtures('load_histogram_record')
+    def test_get_histograms_with_not_exist_id(self):
+        """Get histogram data with not exist id."""
+        test_train_id = 'not_exist_id'
+        processor = HistogramProcessor(self._mock_data_manager)
+        with pytest.raises(TrainJobNotExistError) as exc_info:
+            processor.get_histograms(test_train_id, self._tag_name)
+
+        assert exc_info.value.error_code == '50545005'
+        assert exc_info.value.message == "Train job is not exist. Detail: Can not find the given train job in cache."
+
+    @pytest.mark.usefixtures('load_histogram_record')
+    def test_get_histograms_with_not_exist_tag(self):
+        """Get histogram data with not exist tag."""
+        test_tag_name = 'not_exist_tag_name'
+
+        processor = HistogramProcessor(self._mock_data_manager)
+
+        with pytest.raises(HistogramNotExistError) as exc_info:
+            processor.get_histograms(self._train_id, test_tag_name)
+
+        assert exc_info.value.error_code == '5054500F'
+        assert "Can not find any data in this train job by given tag." in exc_info.value.message
+
+    @pytest.mark.usefixtures('load_histogram_record')
+    def test_get_histograms_success(self):
+        """Get histogram data success."""
+        test_tag_name = self._complete_tag_name
+
+        processor = HistogramProcessor(self._mock_data_manager)
+        results = processor.get_histograms(self._train_id, test_tag_name)
+
+        recv_metadata = results.get('histograms')
+
+        for recv_values, expected_values in zip(recv_metadata, self._histograms):
+            assert recv_values.get('wall_time') == expected_values.get('wall_time')
+            assert recv_values.get('step') == expected_values.get('step')