diff --git a/pyproject.toml b/pyproject.toml
index 6a88d77..499fc87 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -10,7 +10,7 @@ keywords = ['adk', 'agent']
 readme = "README.md"
 requires-python = ">=3.13"
 dependencies = [
-    "google-adk==1.3.0",
+    "google-adk==1.28.1",
     "uvicorn==0.34.3",
     "google-cloud-aiplatform[evaluation]",
 ]