diff --git a/autogen/oai/openai_utils.py b/autogen/oai/openai_utils.py
index e0c4dbbd79..537390109c 100644
--- a/autogen/oai/openai_utils.py
+++ b/autogen/oai/openai_utils.py
@@ -90,7 +90,7 @@ def is_valid_api_key(api_key: str) -> bool:
     Returns:
         bool: A boolean that indicates if input is valid OpenAI API key.
     """
-    api_key_re = re.compile(r"^sk-[A-Za-z0-9]{32,}$")
+    api_key_re = re.compile(r"^sk-(proj-)?[A-Za-z0-9]{32,}$")
     return bool(re.fullmatch(api_key_re, api_key))
 
 
diff --git a/test/oai/test_utils.py b/test/oai/test_utils.py
index 65ec7a014a..8f4dd22145 100755
--- a/test/oai/test_utils.py
+++ b/test/oai/test_utils.py
@@ -382,6 +382,7 @@ def test_is_valid_api_key():
     assert not is_valid_api_key("sk-asajsdjsd22372%23kjdfdfdf2329ffUUDSDS")
     assert is_valid_api_key("sk-asajsdjsd22372X23kjdfdfdf2329ffUUDSDS")
     assert is_valid_api_key("sk-asajsdjsd22372X23kjdfdfdf2329ffUUDSDS1212121221212sssXX")
+    assert is_valid_api_key("sk-proj-asajsdjsd22372X23kjdfdfdf2329ffUUDSDS12121212212")
     assert is_valid_api_key(MOCK_OPEN_AI_API_KEY)