diff --git a/evoagentx/models/litellm_model.py b/evoagentx/models/litellm_model.py
index 9f4fb755..6bc1b723 100644
--- a/evoagentx/models/litellm_model.py
+++ b/evoagentx/models/litellm_model.py
@@ -162,6 +162,7 @@ def single_generate(self, messages: List[dict], **kwargs) -> str:
 
         return output
 
+    @retry(wait=wait_random_exponential(min=1, max=60), stop=stop_after_attempt(5))
     async def single_generate_async(self, messages: List[dict], **kwargs) -> str:
         """
         Generate a single response using the async LiteLLM completion function.
diff --git a/evoagentx/models/openai_model.py b/evoagentx/models/openai_model.py
index 75708ed2..30c47938 100644
--- a/evoagentx/models/openai_model.py
+++ b/evoagentx/models/openai_model.py
@@ -247,6 +247,7 @@ def single_generate(self, messages: List[dict], **kwargs) -> str:
     def batch_generate(self, batch_messages: List[List[dict]], **kwargs) -> List[str]:
         return [self.single_generate(messages=one_messages, **kwargs) for one_messages in batch_messages]
 
+    @retry(wait=wait_random_exponential(min=1, max=60), stop=stop_after_attempt(5))
     async def single_generate_async(self, messages: List[dict], **kwargs) -> str:
 
         stream = kwargs.get("stream", self.config.stream)
diff --git a/evoagentx/models/openrouter_model.py b/evoagentx/models/openrouter_model.py
index e31e140d..c3d13423 100644
--- a/evoagentx/models/openrouter_model.py
+++ b/evoagentx/models/openrouter_model.py
@@ -331,6 +331,7 @@ def single_generate(self, messages: List[dict], **kwargs) -> str:
     def batch_generate(self, batch_messages: List[List[dict]], **kwargs) -> List[str]:
         return [self.single_generate(messages=one_messages, **kwargs) for one_messages in batch_messages]
 
+    @retry(wait=wait_random_exponential(min=1, max=60), stop=stop_after_attempt(5))
     async def single_generate_async(self, messages: List[dict], **kwargs) -> str:
         stream = kwargs.get("stream", self.config.stream)
         output_response = kwargs.get("output_response", self.config.output_response)
diff --git a/tests/src/models/test_async_retry.py b/tests/src/models/test_async_retry.py
new file mode 100644
index 00000000..593f4363
--- /dev/null
+++ b/tests/src/models/test_async_retry.py
@@ -0,0 +1,98 @@
+from collections.abc import Callable
+from typing import Any
+from unittest.mock import AsyncMock
+
+import pytest
+from tenacity import wait_none
+
+from evoagentx.models.litellm_model import LiteLLM
+from evoagentx.models.model_configs import (
+    LiteLLMConfig,
+    OpenAILLMConfig,
+    OpenRouterConfig,
+)
+from evoagentx.models.openai_model import OpenAILLM
+from evoagentx.models.openrouter_model import OpenRouterLLM
+from tests.src.models.mock_response import (
+    get_openai_chat_completion,
+    get_openrouter_chat_completion,
+)
+
+
+def _make_openai_llm() -> OpenAILLM:
+    return OpenAILLM(
+        config=OpenAILLMConfig(
+            model="gpt-4o-mini",
+            openai_key="mock_openai_key",
+            output_response=False,
+        )
+    )
+
+
+def _make_litellm() -> LiteLLM:
+    return LiteLLM(
+        config=LiteLLMConfig(
+            model="gpt-4o-mini",
+            openai_key="mock_openai_key",
+            output_response=False,
+        )
+    )
+
+
+def _make_openrouter_llm() -> OpenRouterLLM:
+    return OpenRouterLLM(
+        config=OpenRouterConfig(
+            model="openai/gpt-4o-mini",
+            openrouter_key="mock_openrouter_key",
+            output_response=False,
+        )
+    )
+
+
+@pytest.mark.parametrize(
+    ("llm_factory", "create_target", "response", "expected"),
+    [
+        (
+            _make_openai_llm,
+            "openai.resources.chat.completions.AsyncCompletions.create",
+            get_openai_chat_completion(),
+            "Beijing",
+        ),
+        (
+            _make_litellm,
+            "evoagentx.models.litellm_model.acompletion",
+            get_openai_chat_completion(),
+            "Beijing",
+        ),
+        (
+            _make_openrouter_llm,
+            "openai.resources.chat.completions.AsyncCompletions.create",
+            get_openrouter_chat_completion(),
+            "Paris",
+        ),
+    ],
+)
+async def test_single_generate_async_retries_transient_failure(
+    mocker,
+    monkeypatch,
+    llm_factory: Callable[[], Any],
+    create_target: str,
+    response: Any,
+    expected: str,
+) -> None:
+    llm = llm_factory()
+    create = mocker.patch(
+        create_target,
+        new_callable=AsyncMock,
+        side_effect=[RuntimeError("transient error"), response],
+    )
+    retry_controller = getattr(type(llm).single_generate_async, "retry", None)
+    assert retry_controller is not None
+    monkeypatch.setattr(retry_controller, "wait", wait_none())
+
+    result = await llm.single_generate_async(
+        messages=[{"role": "user", "content": "hello"}]
+    )
+
+    assert result == expected
+    assert create.await_count == 2