diff --git a/CHANGELOG.md b/CHANGELOG.md
index aec316c..cd96a26 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -44,6 +44,12 @@ Note that 0.3.3 was never released; 0.3.4 follows 0.3.2.
   summaries with their issue links, grouped as in the changelog, and links to
   the full entries on the documentation site. The changelog itself keeps the
   details.
+- **`SessionError` derives from `CacheXError`.** It derived from `Exception`,
+  while `StateError` already derived from `CacheXError`, so `except CacheXError`
+  caught state errors but not session errors. Handlers for `SessionError` or
+  `Exception` keep working. A `try` block that lists `except CacheXError`
+  before `except SessionError` now takes the `CacheXError` branch for session
+  errors. ([#162](https://github.com/allen0099/FastAPI-CacheX/issues/162))
 
 ### Deprecated
 
diff --git a/docs/SESSION.md b/docs/SESSION.md
index 20eee69..32d2340 100644
--- a/docs/SESSION.md
+++ b/docs/SESSION.md
@@ -645,6 +645,8 @@ be sent back to the client. `get_session()` raises a `SessionError` subclass on
 failure: `SessionTokenError` (malformed token), `SessionSecurityError` (bad
 signature or binding mismatch), `SessionNotFoundError`, `SessionInvalidError`
 (session not active) or `SessionExpiredError` (TTL or absolute timeout exceeded).
+Since 0.3.8, `SessionError` derives from `CacheXError`, so `except CacheXError`
+catches session errors too.
 
 Every method with its signature is in the generated
 [Session API reference](api/session.md).
diff --git a/fastapi_cachex/session/exceptions.py b/fastapi_cachex/session/exceptions.py
index 32a2304..4c71b4b 100644
--- a/fastapi_cachex/session/exceptions.py
+++ b/fastapi_cachex/session/exceptions.py
@@ -1,8 +1,14 @@
 """Session-related exceptions."""
 
+from fastapi_cachex.exceptions import CacheXError
 
-class SessionError(Exception):
-    """Base exception for session errors."""
+
+class SessionError(CacheXError):
+    """Base exception for session errors.
+
+    Derives from ``CacheXError`` since 0.3.8, like ``StateError``, so
+    ``except CacheXError`` also catches session errors.
+    """
 
 
 class SessionNotFoundError(SessionError):
diff --git a/i18n/zh-TW/docs/SESSION.md b/i18n/zh-TW/docs/SESSION.md
index 6843232..dc6fc84 100644
--- a/i18n/zh-TW/docs/SESSION.md
+++ b/i18n/zh-TW/docs/SESSION.md
@@ -534,7 +534,7 @@ session, new_token = await manager.regenerate_session_id(session)
 
 ## SessionManager 概覽 {#sessionmanager-at-a-glance}
 
-`SessionManager(backend, config, token_serializer=None)` 處理整個生命週期：`create_session()`／`create_anonymous_session()` 回傳 `(session, token)`；`get_session()` 回傳 `(session, renewed_token)`，其中 `renewed_token` 只有在滑動過期更新了權杖時才會有值，並應傳回給用戶端。`get_session()` 失敗時會拋出 `SessionError` 的子類別：`SessionTokenError`（權杖格式錯誤）、`SessionSecurityError`（簽章錯誤或綁定不符）、`SessionNotFoundError`、`SessionInvalidError`（Session 不是啟用狀態）或 `SessionExpiredError`（超過 TTL 或絕對逾時）。
+`SessionManager(backend, config, token_serializer=None)` 處理整個生命週期：`create_session()`／`create_anonymous_session()` 回傳 `(session, token)`；`get_session()` 回傳 `(session, renewed_token)`，其中 `renewed_token` 只有在滑動過期更新了權杖時才會有值，並應傳回給用戶端。`get_session()` 失敗時會拋出 `SessionError` 的子類別：`SessionTokenError`（權杖格式錯誤）、`SessionSecurityError`（簽章錯誤或綁定不符）、`SessionNotFoundError`、`SessionInvalidError`（Session 不是啟用狀態）或 `SessionExpiredError`（超過 TTL 或絕對逾時）。從 0.3.8 起，`SessionError` 繼承自 `CacheXError`，因此 `except CacheXError` 也會捕捉 Session 錯誤。
 
 每個方法及其簽名請見自動產生的 [Session API 參考](https://fastapi-cachex.readthedocs.io/en/latest/api/session/)（英文）。
 
diff --git a/tests/session/test_manager.py b/tests/session/test_manager.py
index 92918af..265aa13 100644
--- a/tests/session/test_manager.py
+++ b/tests/session/test_manager.py
@@ -11,6 +11,7 @@
 from pydantic import SecretStr
 
 from fastapi_cachex.backends.memory import MemoryBackend
+from fastapi_cachex.exceptions import CacheXError
 from fastapi_cachex.session.config import SessionConfig
 from fastapi_cachex.session.exceptions import SessionExpiredError
 from fastapi_cachex.session.exceptions import SessionInvalidError
@@ -120,6 +121,17 @@ async def test_get_invalid_token(manager: SessionManager) -> None:
         await manager.get_session("invalid-token")
 
 
+@pytest.mark.asyncio
+async def test_session_errors_are_caught_as_cachex_errors(
+    manager: SessionManager,
+) -> None:
+    """Test a session error is caught by ``except CacheXError`` (#162)."""
+    with pytest.raises(CacheXError) as exc_info:
+        await manager.get_session("invalid-token")
+
+    assert isinstance(exc_info.value, SessionTokenError)
+
+
 @pytest.mark.asyncio
 async def test_get_nonexistent_session(manager: SessionManager) -> None:
     """Test getting nonexistent session."""