diff --git a/backend/requirements.txt b/backend/requirements.txt
index 06d1775..840bdb9 100644
--- a/backend/requirements.txt
+++ b/backend/requirements.txt
@@ -13,7 +13,7 @@ httpx>=0.26.0
 # LangChain / LangGraph
 langchain>=1.0.0
 langchain-core>=1.0.0
-langchain-google-genai>=2.0.0
+langchain-google-genai>=4.2.5
 langgraph>=0.6.0
 langgraph-prebuilt>=0.6.0