diff --git a/tests/python_client/chaos/chaos_test.sh b/tests/python_client/chaos/chaos_test.sh
index a36a8ce341..b05054fcf8 100644
--- a/tests/python_client/chaos/chaos_test.sh
+++ b/tests/python_client/chaos/chaos_test.sh
@@ -21,6 +21,7 @@ kubectl config set-context --current --namespace=${ns}
 pod=${1:-"querynode"}
 chaos_type=${2:-"pod_kill"} #pod_kill or pod_failure
 chaos_task=${3:-"chaos-test"} # chaos-test or data-consist-test 
+node_num=${4:-1} # cluster_1_node or cluster_n_nodes
 
 release="test"-${pod}-${chaos_type/_/-} # replace pod_kill to pod-kill
 
@@ -40,11 +41,13 @@ then
     echo "install standalone"
     helm install --wait --timeout 360s ${release} milvus/milvus --set service.type=NodePort -f ../standalone-values.yaml -n=${ns}
 fi
-# if chaos_type is pod_failure, update replicas
-if [ "$chaos_type" == "pod_failure" ];
+
+declare -A pod_map=(["querynode"]="queryNode" ["indexnode"]="indexNode" ["datanode"]="dataNode" ["proxy"]="proxy")
+
+if [ "$node_num" -gt "1" ];
 then
-    declare -A pod_map=(["querynode"]="queryNode" ["indexnode"]="indexNode" ["datanode"]="dataNode" ["proxy"]="proxy")
-    helm upgrade ${release} milvus/milvus --set ${pod_map[${pod}]}.replicas=2 --reuse-values
+    echo "install cluster n node"
+    helm upgrade ${release} milvus/milvus --set ${pod_map[${pod}]}.replicas=$node_num --reuse-values
 fi
 
 # wait all pod ready