diff --git a/README.md b/README.md
index bbc2d8f..e185cbf 100644
--- a/README.md
+++ b/README.md
@@ -1,2 +1,59 @@
-# osschat-milvus
+# ANN Search Operator: MilvusClient
 
+*author: junjie.jiangjjj*
+
+<br />
+
+## Desription
+Search embedding in [Milvus](https://milvus.io/), **please make sure you have inserted data to Milvus Collection**.
+
+<br />
+
+
+
+## Code Example
+
+> Please make sure you have inserted data into Milvus and [load the collection](https://milvus.io/docs/v2.1.x/load_collection.md) to memory.
+
+
+```python
+from towhee import pipe, ops, DataCollection
+
+p = pipe.input('collection_name', 'text')  \
+    .map('text', 'vec', ops.sentence_embedding.transformers(model_name='all-MiniLM-L12-v2'))  \
+    .flat_map(('collection_name', 'vec'), 'rows', ops.ann_search.milvus_client(host='127.0.0.1', port='19530', **{'output_fields': ['text']}))  \
+    .map('rows', ('id', 'score', 'text'), lambda x: (x[0], x[1], x[2]))  \
+    .output('id', 'score', 'text')
+
+DataCollection(p('test_collection', 'cat')).show()
+
+# result:
+
+```
+
+```python
+from towhee import pipe, ops
+
+# search additional info url:
+from towhee import pipe, ops, DataCollection
+
+p = pipe.input('collection_name', 'text')  \
+    .map('text', 'vec', ops.sentence_embedding.transformers(model_name='all-MiniLM-L12-v2'))  \
+    .map(('collection_name', 'vec'), 'rows', ops.ann_search.milvus_client(host='127.0.0.1', port='19530', **{'output_fields': ['text']}))  \
+    .output('rows')
+
+DataCollection(p('test_collection', 'cat')).show()
+```
+
+<br />
+
+
+
+## Factory Constructor
+
+Create the operator via the following factory method:
+
+***ann_search.milvus_client(host='127.0.0.1', port='19530')***
+
+
+<br />
diff --git a/__init__.py b/__init__.py
new file mode 100644
index 0000000..1f73cb7
--- /dev/null
+++ b/__init__.py
@@ -0,0 +1,5 @@
+from .milvus_client import MilvusClient
+
+
+def osschat_milvus(*args, **kwargs):
+    return MilvusClient(*args, **kwargs)
diff --git a/milvus_client.py b/milvus_client.py
new file mode 100644
index 0000000..fb1cce2
--- /dev/null
+++ b/milvus_client.py
@@ -0,0 +1,102 @@
+from pymilvus import connections, Collection
+from towhee.operator import PyOperator, SharedType
+import uuid
+
+
+class MilvusClient(PyOperator):
+    """
+    Search for embedding vectors in Milvus. Note that the Milvus collection has data before searching,
+
+    Args:
+        collection (`str`):
+            The collection name.
+        kwargs
+            The kwargs with collection.search, refer to https://milvus.io/docs/v2.0.x/search.md#Prepare-search-parameters.
+            And the `anns_field` defaults to the vector field name, `limit` defaults to 10, and `metric_type` in `param` defaults to 'L2'
+            if there has no index(FLAT), and for default index `param`:
+                IVF_FLAT: {"params": {"nprobe": 10}},
+                IVF_SQ8: {"params": {"nprobe": 10}},
+                IVF_PQ: {"params": {"nprobe": 10}},
+                HNSW: {"params": {"ef": 10}},
+                IVF_HNSW: {"params": {"nprobe": 10, "ef": 10}},
+                RHNSW_FLAT: {"params": {"ef": 10}},
+                RHNSW_SQ: {"params": {"ef": 10}},
+                RHNSW_PQ: {"params": {"ef": 10}},
+                ANNOY: {"params": {"search_k": 10}}.
+    """
+
+    def __init__(self, host: str = 'localhost', port: int = 19530,
+                 user: str = None, password: str = None, **kwargs):
+        """
+        Get an existing collection.
+        """
+        self._host = host
+        self._port = port
+        self.kwargs = kwargs
+        self._connect_name = uuid.uuid4().hex
+        if None in [user, password]:
+            connections.connect(alias=self._connect_name, host=self._host, port=self._port)
+        else:
+            connections.connect(alias=self._connect_name, host=self._host, port=self._port,
+                                user=user, password=password, secure=True)
+        
+
+    def __call__(self, collection_name: str, query: 'ndarray'):
+        self._collection = Collection(collection_name, using=self._connect_name)
+        if 'anns_field' not in self.kwargs:
+            fields_schema = self._collection.schema.fields
+            for schema in fields_schema:
+                if schema.dtype in (101, 100):
+                    self.kwargs['anns_field'] = schema.name
+        if 'limit' not in self.kwargs:
+            self.kwargs['limit'] = 10
+        index_params = {
+            'FLAT': {'params': {'nprobe': 10}},
+            'IVF_FLAT': {'params': {'nprobe': 10}},
+            'IVF_SQ8': {'params': {'nprobe': 10}},
+            'IVF_PQ': {'params': {'nprobe': 10}},
+            'HNSW': {'params': {'ef': 10}},
+            'RHNSW_FLAT': {'params': {'ef': 10}},
+            'RHNSW_SQ': {'params': {'ef': 10}},
+            'RHNSW_PQ': {'params': {'ef': 10}},
+            'IVF_HNSW': {'params': {'nprobe': 10, 'ef': 10}},
+            'ANNOY': {'params': {'search_k': 10}},
+            'AUTOINDEX': {}
+        }
+        if 'param' not in self.kwargs:
+            if len(self._collection.indexes) != 0:
+                index_type = self._collection.indexes[0].params['index_type']
+                self.kwargs['param'] = index_params[index_type]
+            else:
+                self.kwargs['param'] = index_params['IVF_FLAT']
+            if 'metric_type' in self.kwargs:
+                self.kwargs['param']['metric_type'] = self.kwargs['metric_type']
+            else:
+                self.kwargs['param']['metric_type'] = 'L2'
+        
+        self._collection.load()
+        milvus_result = self._collection.search(
+            data=[query],
+            **self.kwargs
+        )
+
+        result = []
+        for hit in milvus_result[0]:
+            row = []
+            row.extend([hit.id, hit.score])
+            if 'output_fields' in self.kwargs:
+                for k in self.kwargs['output_fields']:
+                 row.append(hit.entity.get(k))
+            result.append(row)
+        return result
+
+    @property
+    def shared_type(self):
+        return SharedType.NotShareable
+
+    # def __del__(self):
+    #     if connections.has_connection(self._connect_name):
+    #         try:
+    #             connections.disconnect(self._connect_name)
+    #         except:
+    #             pass
diff --git a/requirements.txt b/requirements.txt
new file mode 100644
index 0000000..e0472f0
--- /dev/null
+++ b/requirements.txt
@@ -0,0 +1 @@
+pymilvus