diff --git a/lightrag/lightrag.py b/lightrag/lightrag.py
index 5bb05764..990c1bcf 100644
--- a/lightrag/lightrag.py
+++ b/lightrag/lightrag.py
@@ -184,7 +184,7 @@ class LightRAG:
     """Maximum number of concurrent embedding function calls."""
 
     embedding_cache_config: dict[str, Any] = field(
-        default={
+        default_factory= lambda: {
             "enabled": False,
             "similarity_threshold": 0.95,
             "use_llm_check": False,