diff --git a/contributing/samples/adk_knowledge_agent/requirements.txt b/contributing/samples/adk_knowledge_agent/requirements.txt
index 6e25bba625..a5e87aacff 100644
--- a/contributing/samples/adk_knowledge_agent/requirements.txt
+++ b/contributing/samples/adk_knowledge_agent/requirements.txt
@@ -1 +1 @@
-google-adk[a2a]==1.15.1
+google-adk[a2a]==1.28.1
diff --git a/contributing/samples/authn-adk-all-in-one/adk_agents/requirements.txt b/contributing/samples/authn-adk-all-in-one/adk_agents/requirements.txt
index f490d72da0..248e6cd503 100644
--- a/contributing/samples/authn-adk-all-in-one/adk_agents/requirements.txt
+++ b/contributing/samples/authn-adk-all-in-one/adk_agents/requirements.txt
@@ -1 +1 @@
-google-adk==1.12
+google-adk==1.28.1
diff --git a/contributing/samples/authn-adk-all-in-one/requirements.txt b/contributing/samples/authn-adk-all-in-one/requirements.txt
index d5bc65a788..671a94f93f 100644
--- a/contributing/samples/authn-adk-all-in-one/requirements.txt
+++ b/contributing/samples/authn-adk-all-in-one/requirements.txt
@@ -1,6 +1,6 @@
-google-adk==1.12
+google-adk==1.28.1
 Flask==3.1.3
 flask-cors==6.0.1
 python-dotenv==1.1.1
 PyJWT[crypto]==2.10.1
-requests==2.32.4
+requests==2.33.0