diff --git a/fastapi/encoders.py b/fastapi/encoders.py
index c9f882d2ba..ea6c4ea6d3 100644
--- a/fastapi/encoders.py
+++ b/fastapi/encoders.py
@@ -280,11 +280,13 @@ def jsonable_encoder(
         return None
     if isinstance(obj, dict):
         encoded_dict = {}
-        allowed_keys = set(obj.keys())
-        if include is not None:
-            allowed_keys &= set(include)
-        if exclude is not None:
-            allowed_keys -= set(exclude)
+        allowed_keys: set[Any] | None = None
+        if include is not None or exclude is not None:
+            allowed_keys = set(obj.keys())
+            if include is not None:
+                allowed_keys &= set(include)
+            if exclude is not None:
+                allowed_keys -= set(exclude)
         for key, value in obj.items():
             if (
                 (
@@ -293,7 +295,7 @@ def jsonable_encoder(
                     or (not key.startswith("_sa"))
                 )
                 and (value is not None or not exclude_none)
-                and key in allowed_keys
+                and (allowed_keys is None or key in allowed_keys)
             ):
                 encoded_key = jsonable_encoder(
                     key,
diff --git a/tests/test_jsonable_encoder.py b/tests/test_jsonable_encoder.py
index c23a9e5d79..a542c02c65 100644
--- a/tests/test_jsonable_encoder.py
+++ b/tests/test_jsonable_encoder.py
@@ -82,6 +82,9 @@ def test_encode_dict():
         "name": "Firulais",
         "owner": {"name": "Foo"},
     }
+    assert jsonable_encoder(pet, include={"name", "owner"}, exclude={"owner"}) == {
+        "name": "Firulais"
+    }
 
 
 def test_encode_dict_include_exclude_list():