diff --git a/dialogy/preprocess/text/duckling_plugin.py b/dialogy/preprocess/text/duckling_plugin.py
index 1a493549..0b4fda6d 100644
--- a/dialogy/preprocess/text/duckling_plugin.py
+++ b/dialogy/preprocess/text/duckling_plugin.py
@@ -114,6 +114,7 @@ def __init__(
         url: str = "http://0.0.0.0:8000/parse",
         access: Optional[PluginFn] = None,
         mutate: Optional[PluginFn] = None,
+        custom_entity_map: Optional[Dict[str, Any]] = None,
         debug: bool = False,
     ) -> None:
         """
@@ -129,6 +130,11 @@ def __init__(
             "Content-Type": "application/x-www-form-urlencoded; charset=UTF-8"
         }
 
+        if isinstance(custom_entity_map, dict):
+            self.dimension_entity_map = {**dimension_entity_map, **custom_entity_map}
+        else:
+            self.dimension_entity_map = dimension_entity_map
+
     def __set_timezone(self) -> Optional[BaseTzInfo]:
         """
         Set timezone as BaseTzInfo from compatible timezone string.
@@ -214,9 +220,9 @@ def _reshape(
                     if entity[EntityKeys.VALUE][EntityKeys.TYPE] == EntityKeys.INTERVAL:
                         # Duckling entities with interval type have a different structure for value(s).
                         # They have a need to express units in "from", "to" format.
-                        cls = dimension_entity_map[entity[EntityKeys.DIM]][EntityKeys.INTERVAL]  # type: ignore
+                        cls = self.dimension_entity_map[entity[EntityKeys.DIM]][EntityKeys.INTERVAL]  # type: ignore
                     else:
-                        cls = dimension_entity_map[entity[EntityKeys.DIM]][EntityKeys.VALUE]  # type: ignore
+                        cls = self.dimension_entity_map[entity[EntityKeys.DIM]][EntityKeys.VALUE]  # type: ignore
                     # The most appropriate class is picked for making an object from the dict.
                     duckling_entity = cls.from_dict(entity)
                     # Depending on the type of entity, the value is searched and filled.
diff --git a/tests/preprocess/text/test_duckling_plugin.py b/tests/preprocess/text/test_duckling_plugin.py
index 1ba56c08..56114d17 100644
--- a/tests/preprocess/text/test_duckling_plugin.py
+++ b/tests/preprocess/text/test_duckling_plugin.py
@@ -4,11 +4,26 @@
 import pytest
 
 from dialogy.preprocess.text.duckling_plugin import DucklingPlugin
+from dialogy.types import BaseEntity
 from dialogy.workflow import Workflow
 from tests import EXCEPTIONS, load_tests, request_builder
 
 
-# == Test missing i/o ==
+def test_plugin_with_custom_entity_map() -> None:
+    """
+    Here we are checking if the plugin has access to workflow.
+    Since we haven't provided `access`, `mutate` to `DucklingPlugin`
+    we will receive a `TypeError`.
+    """
+    parser = DucklingPlugin(
+        locale="en_IN",
+        timezone="Asia/Kolkata",
+        dimensions=["time"],
+        custom_entity_map={"number": {"value": BaseEntity}},
+    )
+    assert parser.dimension_entity_map["number"]["value"] == BaseEntity
+
+
 def test_plugin_io_missing() -> None:
     """
     Here we are checking if the plugin has access to workflow.