diff --git a/src/frontend_service/requirements.txt b/src/frontend_service/requirements.txt
index f210fab..155288d 100644
--- a/src/frontend_service/requirements.txt
+++ b/src/frontend_service/requirements.txt
@@ -4,7 +4,7 @@ google-cloud-aiplatform[rapid_evaluation]==1.62.0
 itsdangerous==2.2.0
 jinja2==3.1.4
 langchain-community==0.2.19
-langchain==0.2.11
+langchain==0.3.9
 langchain-google-vertexai==1.0.7
 markdown==3.5.2
 types-Markdown==3.5.0.20240129
diff --git a/src/retrieval_service/requirements.txt b/src/retrieval_service/requirements.txt
index dc5589e..48928ee 100644
--- a/src/retrieval_service/requirements.txt
+++ b/src/retrieval_service/requirements.txt
@@ -2,7 +2,7 @@ asyncpg==0.30.0
 fastapi==0.115.3
 google-cloud-firestore==2.19.0
 google-cloud-aiplatform==1.70.0
-langchain==0.3.4
+langchain==0.3.9
 langchain-core==0.3.12
 langchain-google-vertexai==2.0.5
 pgvector==0.3.5