diff --git a/src/main/java/org/redisson/RedissonKeys.java b/src/main/java/org/redisson/RedissonKeys.java
index ca91d8356..63bb821d0 100644
--- a/src/main/java/org/redisson/RedissonKeys.java
+++ b/src/main/java/org/redisson/RedissonKeys.java
@@ -116,6 +116,9 @@ public class RedissonKeys implements RKeys {
                 if (removeExecuted) {
                     throw new IllegalStateException("Element been already deleted");
                 }
+                if (iter == null) {
+                    throw new IllegalStateException();
+                }
 
                 iter.remove();
                 delete(value);
diff --git a/src/main/java/org/redisson/RedissonSet.java b/src/main/java/org/redisson/RedissonSet.java
index 13343a60f..6e2a94400 100644
--- a/src/main/java/org/redisson/RedissonSet.java
+++ b/src/main/java/org/redisson/RedissonSet.java
@@ -115,9 +115,10 @@ public class RedissonSet<V> extends RedissonExpirable implements RSet<V> {
                 if (removeExecuted) {
                     throw new IllegalStateException("Element been already deleted");
                 }
+                if (iter == null) {
+                    throw new IllegalStateException();
+                }
 
-                // lazy init iterator
-//                hasNext();
                 iter.remove();
                 RedissonSet.this.remove(value);
                 removeExecuted = true;