diff --git a/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt b/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
index 3f12cec4242..5c0633354c0 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
+++ b/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
@@ -473,6 +473,9 @@ Release 2.7.0 - UNRELEASED
 
     HDFS-7374. Allow decommissioning of dead DataNodes. (Zhe Zhang)
 
+    HDFS-7403. Inaccurate javadoc of  BlockUCState#COMPLETE state. (
+    Yongjun Zhang via yliu)
+
 Release 2.6.1 - UNRELEASED
 
   INCOMPATIBLE CHANGES
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/common/HdfsServerConstants.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/common/HdfsServerConstants.java
index 3e8c842b34e..9bba2c950b8 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/common/HdfsServerConstants.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/common/HdfsServerConstants.java
@@ -280,8 +280,11 @@ public final class HdfsServerConstants {
   static public enum BlockUCState {
     /**
      * Block construction completed.<br>
-     * The block has at least one {@link ReplicaState#FINALIZED} replica,
-     * and is not going to be modified.
+     * The block has at least the configured minimal replication number
+     * of {@link ReplicaState#FINALIZED} replica(s), and is not going to be
+     * modified.
+     * NOTE, in some special cases, a block may be forced to COMPLETE state,
+     * even if it doesn't have required minimal replications.
      */
     COMPLETE,
     /**