diff --git a/tests/mongo/test_mongo.py b/tests/mongo/test_mongo.py
index 84fe0fe57..c30940ff0 100644
--- a/tests/mongo/test_mongo.py
+++ b/tests/mongo/test_mongo.py
@@ -156,6 +156,7 @@ def list_database_names(self):
     snock = mocker.patch("pymongo.MongoClient")
     snock.return_value = MongoMock("toucan", "test_col")
     aggregate = mocker.patch("pymongo.collection.Collection.aggregate")
+    aggregate.return_value = [{"foo": 42}]
 
     mongo_connector = MongoConnector(name="mycon", host="localhost", port=22, username="ubuntu", password="ilovetoucan")
 
diff --git a/toucan_connectors/mongo/mongo_connector.py b/toucan_connectors/mongo/mongo_connector.py
index bc5ce4ad5..519d59d90 100644
--- a/toucan_connectors/mongo/mongo_connector.py
+++ b/toucan_connectors/mongo/mongo_connector.py
@@ -1,3 +1,4 @@
+import itertools
 from collections.abc import Generator
 from contextlib import contextmanager
 from functools import _lru_cache_wrapper, cached_property, lru_cache
@@ -260,15 +261,22 @@ def _execute_query(self, data_source: MongoDataSource):
             col = client[data_source.database][data_source.collection]
             return col.aggregate(data_source.query)  # type: ignore[arg-type]
 
-    def _retrieve_data(self, data_source):
+    def _retrieve_data(self, data_source, chunk_size: int | None = None):
         data_source.query = normalize_query(data_source.query, data_source.parameters)
         data = self._execute_query(data_source)
-        return pd.DataFrame(list(data))
+
+        if chunk_size:
+            chunks = []
+            while (chunk := list(itertools.islice(data, chunk_size))):
+                chunks.append(pd.DataFrame.from_records(chunk))
+            return pd.concat(chunks) if chunks else pd.DataFrame()
+        else:
+            return pd.DataFrame.from_records(data)
 
     @decorate_func_with_retry
-    def get_df(self, data_source, permissions=None):
+    def get_df(self, data_source, permissions=None, chunk_size: int | None = None):
         data_source.query = apply_condition_filter(data_source.query, permissions)
-        return self._retrieve_data(data_source)
+        return self._retrieve_data(data_source, chunk_size=chunk_size)
 
     @decorate_func_with_retry
     def get_slice(
@@ -278,6 +286,7 @@ def get_slice(
         offset: int = 0,
         limit: int | None = None,
         get_row_count: bool | None = False,
+        chunk_size: int | None = None,
     ) -> DataSlice:
         # Create a copy in order to keep the original (deepcopy-like)
         data_source = data_source.model_copy(deep=True)
@@ -310,7 +319,7 @@ def get_slice(
             total_count = res["count"][0]["value"] if len(res["count"]) > 0 else 0
             df = pd.DataFrame(res["df"])
         else:
-            df = self.get_df(data_source, permissions)
+            df = self.get_df(data_source, permissions, chunk_size=chunk_size)
             total_count = len(df)
             # We try to remove the _id from this DataFrame if there is one
             # ugly for now but we need to handle that in this else case