diff --git a/hadoop-yarn-project/CHANGES.txt b/hadoop-yarn-project/CHANGES.txt
index f4f62e04328..e880471a4be 100644
--- a/hadoop-yarn-project/CHANGES.txt
+++ b/hadoop-yarn-project/CHANGES.txt
@@ -940,6 +940,9 @@ Release 2.6.3 - UNRELEASED
 
     YARN-4424. Fix deadlock in RMAppImpl. (Jian he via wangda)
 
+    YARN-4434. NodeManager Disk Checker parameter documentation is not correct.
+    (Weiwei Yang via aajisaka)
+
 Release 2.6.2 - 2015-10-28
 
   INCOMPATIBLE CHANGES
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-site/src/site/markdown/NodeManager.md b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-site/src/site/markdown/NodeManager.md
index 6341c607f06..87b9acb5819 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-site/src/site/markdown/NodeManager.md
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-site/src/site/markdown/NodeManager.md
@@ -39,7 +39,7 @@ The NodeManager runs services to determine the health of the node it is executin
 | `yarn.nodemanager.disk-health-checker.enable` | true, false | Enable or disable the disk health checker service |
 | `yarn.nodemanager.disk-health-checker.interval-ms` | Positive integer | The interval, in milliseconds, at which the disk checker should run; the default value is 2 minutes |
 | `yarn.nodemanager.disk-health-checker.min-healthy-disks` | Float between 0-1 | The minimum fraction of disks that must pass the check for the NodeManager to mark the node as healthy; the default is 0.25 |
-| `yarn.nodemanager.disk-health-checker.max-disk-utilization-per-disk-percentage` | Float between 0-100 | The maximum percentage of disk space that may be utilized before a disk is marked as unhealthy by the disk checker service. This check is run for every disk used by the NodeManager. The default value is 100 i.e. the entire disk can be used. |
+| `yarn.nodemanager.disk-health-checker.max-disk-utilization-per-disk-percentage` | Float between 0-100 | The maximum percentage of disk space that may be utilized before a disk is marked as unhealthy by the disk checker service. This check is run for every disk used by the NodeManager. The default value is 90 i.e. 90% of the disk can be used. |
 | `yarn.nodemanager.disk-health-checker.min-free-space-per-disk-mb` | Integer | The minimum amount of free space that must be available on the disk for the disk checker service to mark the disk as healthy. This check is run for every disk used by the NodeManager. The default value is 0 i.e. the entire disk can be used. |