diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/master/AssignmentManager.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/master/AssignmentManager.java
index b594cba6526..2b72fd3cbff 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/master/AssignmentManager.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/master/AssignmentManager.java
@@ -2298,7 +2298,7 @@ public class AssignmentManager extends ZooKeeperListener {
         // Region is not in transition.
         // We can unassign it only if it's not SPLIT/MERGED.
         state = regionStates.getRegionState(encodedName);
-        if (state.isMerged() || state.isSplit()) {
+        if (state != null && (state.isMerged() || state.isSplit())) {
           LOG.info("Attempting to unassign " + state + ", ignored");
           return;
         }