diff --git a/README.md b/README.md
index 2c42d7a..0553c9b 100644
--- a/README.md
+++ b/README.md
@@ -1,2 +1,78 @@
-# osschat-index
+# ElasticSearch Index
 
+*author: Jael*
+
+<br />
+
+## Description
+
+The index operator index the given documents in ElasticSearch to get ready for retrieval.
+It accepts a single document in dictionary or a list of documents (dictionaries) as input.
+For each document, the index automatically generates a unique id.
+To use this operator, you need to [set up ElasticSearch](https://www.elastic.co/guide/en/elasticsearch/reference/current/setup.html) in advance.
+
+<br />
+
+## Code Example
+
+Insert an example document into ElasticSearch with address of localhost:9200 and index of 'test_index'.
+
+```python
+from datetime import datetime
+from towhee import pipe, ops, DataCollection
+
+
+example_doc = {
+    'title': 'Test Title',
+    'author': 'Towhee',
+    'content': 'This is an example.',
+    'timestamp': datetime.now()
+    }
+
+es_insert = (
+    pipe.input('index_name', 'doc')
+        .map(('index_name', 'doc'), 'res', ops.elasticsearch.index_client(
+            host='localhost', port=9200
+        ))
+        .output('doc', 'res')
+)
+
+res = es_insert('test_index', example_doc) # OR: es_insert('test_index', [example_doc])
+DataCollection(res).show() # Optional: display output data
+```
+
+<br />
+
+## Factory Constructor
+
+Create the operator via the following factory method:
+
+***elasticsearch.search(host='localhost', port=9200, user=None, password=None, ca_certs=None)***
+
+**Parameters:**
+
+***host***: *str*
+
+The host to connect ElasticSearch client.
+
+***port***: *int*
+
+The port to connect ElasticSearch client.
+
+***user***: *str*
+
+The username to connect ElasticSearch client if needed, defaults to None.
+
+***password***: *str*
+
+The user password to connect ElasticSearch client if needed, defaults to None.
+
+***ca_certs***: *str*
+
+The path to CA certificates to connect ElasticSearch client if needed, defaults to None.
+
+<br />
+
+**Returns:**
+
+Index response wrapped by `elastic_transport.ObjectApiResponse`.
diff --git a/__init__.py b/__init__.py
new file mode 100644
index 0000000..9d33678
--- /dev/null
+++ b/__init__.py
@@ -0,0 +1,4 @@
+from .es_index import ESIndex
+
+def osschat_index(*args, **kwargs):
+    return ESIndex(*args, **kwargs)
\ No newline at end of file
diff --git a/es_index.py b/es_index.py
new file mode 100644
index 0000000..c7128f4
--- /dev/null
+++ b/es_index.py
@@ -0,0 +1,107 @@
+import logging
+from typing import Union, List
+
+from elasticsearch import Elasticsearch
+import elasticsearch.helpers # type: ignore
+
+from towhee.operator import PyOperator, SharedType # type: ignore
+
+
+logger = logging.getLogger()
+
+
+class ESIndex(PyOperator):
+    """
+    Use bulk to insert docs into ElasticSearch index, using auto id generated.
+
+    Args:
+        host (`str`): host to connect ElasticSearch client
+        port (`int`): port to connect ElasticSearch client
+        user (`str=None`): user name to connect ElasticSearch client, defaults to None
+        password (`str=None`): user password to connect ElasticSearch client, defaults to None
+        ca_certs (`str=None`): path to CA certificate, defaults to None
+    """
+    def __init__(self, host: str, port: int, user: str = None, password: str = None, ca_certs: str = None):
+        super().__init__()
+        try:
+            self.client = Elasticsearch(
+                f'https://{host}:{port}',
+                ca_certs=ca_certs,
+                basic_auth=(user, password))
+            logger.info('Successfully connected to ElasticSearch client.')
+        except Exception as e:
+            logger.error('Failed to connect ElasticSearch client:\n', e)
+            raise e
+
+
+    def __call__(self, index_name: str, doc: Union[dict, List[dict]]):
+        # if index not exist, create with stop words analyzer to strengthen the search accuracy
+        if not self.is_index_exist(index_name):
+            logger.info(f'index{index_name} not exists, will create the index with stopwords analyzer')
+            self.create_index_with_stopwords(index_name)
+
+        if isinstance(doc, dict):
+            docs = [doc]
+        else:
+            docs = doc
+
+        for x in docs:
+            assert isinstance(x, dict)
+
+        actions = [
+            {
+                '_op_type': 'index',
+                '_index': index_name,
+                '_source': docs[i] 
+            }
+            for i in range(len(docs))
+        ]
+        res = elasticsearch.helpers.bulk(self.client, actions, refresh=True)
+        return res
+
+    def is_index_exist(self, index_name: str):
+        return self.client.indices.exists(index=index_name)
+
+    def create_index_with_stopwords(self, index_name: str):
+        mappings = {
+            "properties": {
+                "milvus_id": {
+                    "type": "long"
+                },
+                "paragraph": {
+                    "type": "text",
+                    "analyzer": "my_stop_analyzer",
+                    "fields": {
+                        "keyword": {
+                            "type": "keyword",
+                            "ignore_above": 256
+                        }
+                    }
+                },
+                "path": {
+                    "type": "text",
+                    "analyzer": "my_stop_analyzer",
+                    "fields": {
+                        "keyword": {
+                            "type": "keyword",
+                            "ignore_above": 256
+                        }
+                    }
+                }
+            }
+        }
+        settings = {
+            "analysis": {
+                "analyzer": {
+                    "my_stop_analyzer": {
+                        "type": "stop",
+                        "stopwords_path": "stopwords/stopwords-en.txt"
+                    }
+                }
+            },
+            "number_of_shards": 3,
+            "number_of_replicas": 0
+        }
+        self.client.indices.create(index=index_name, mappings=mappings, settings=settings)
+        logger.info(f"created index{index_name}")
+