diff --git a/src/claude_code_sdk/types.py b/src/claude_code_sdk/types.py
index fe905d565..88c3d42c9 100644
--- a/src/claude_code_sdk/types.py
+++ b/src/claude_code_sdk/types.py
@@ -7,7 +7,7 @@
 from typing_extensions import NotRequired  # For Python < 3.11 compatibility
 
 # Permission modes
-PermissionMode = Literal["default", "acceptEdits", "bypassPermissions"]
+PermissionMode = Literal["default", "acceptEdits", "plan", "bypassPermissions"]
 
 
 # MCP Server config
diff --git a/tests/test_types.py b/tests/test_types.py
index 604629235..816327ce5 100644
--- a/tests/test_types.py
+++ b/tests/test_types.py
@@ -83,6 +83,15 @@ def test_claude_code_options_with_permission_mode(self):
         options = ClaudeCodeOptions(permission_mode="bypassPermissions")
         assert options.permission_mode == "bypassPermissions"
 
+        options_plan = ClaudeCodeOptions(permission_mode="plan")
+        assert options_plan.permission_mode == "plan"
+
+        options_default = ClaudeCodeOptions(permission_mode="default")
+        assert options_default.permission_mode == "default"
+
+        options_accept = ClaudeCodeOptions(permission_mode="acceptEdits")
+        assert options_accept.permission_mode == "acceptEdits"
+
     def test_claude_code_options_with_system_prompt(self):
         """Test Options with system prompt."""
         options = ClaudeCodeOptions(