diff --git a/hbase0.98/hbase-manager-0.98/src/main/java/com/kakao/hbase/manager/command/BalanceRule.java b/hbase0.98/hbase-manager-0.98/src/main/java/com/kakao/hbase/manager/command/BalanceRule.java
index ecf3d42..ad31244 100644
--- a/hbase0.98/hbase-manager-0.98/src/main/java/com/kakao/hbase/manager/command/BalanceRule.java
+++ b/hbase0.98/hbase-manager-0.98/src/main/java/com/kakao/hbase/manager/command/BalanceRule.java
@@ -105,7 +105,10 @@ private static List<RegionPlan> makeStochasticPlan(
 
         Map<HRegionInfo, ServerName> regionAssignmentMap = Balance.getRegionAssignmentMap(admin, tableNameSet);
         for (Map.Entry<HRegionInfo, ServerName> entry : regionAssignmentMap.entrySet()) {
-            clusterState.get(entry.getValue()).add(entry.getKey());
+            List<HRegionInfo> hRegionInfos = clusterState.get(entry.getValue());
+            if (hRegionInfos != null) {
+                hRegionInfos.add(entry.getKey());
+            }
         }
 
         Configuration conf = admin.getConfiguration();