diff --git a/samples/langchain_on_vertexai/requirements.txt b/samples/langchain_on_vertexai/requirements.txt
index f841a4c3..064bf76a 100644
--- a/samples/langchain_on_vertexai/requirements.txt
+++ b/samples/langchain_on_vertexai/requirements.txt
@@ -1,4 +1,4 @@
-google-cloud-aiplatform[reasoningengine,langchain]==1.120.0
+google-cloud-aiplatform[reasoningengine,langchain]==1.121.0
 google-cloud-resource-manager==1.14.2
 langchain-community==0.3.31
 langchain-google-cloud-sql-pg==0.14.1