diff --git a/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt b/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
index fcc02d27c5..47f931f221 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
+++ b/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
@@ -350,6 +350,9 @@ Release 2.4.0 - UNRELEASED
 
     HDFS-5882. TestAuditLogs is flaky (jxiang via cmccabe)
 
+    HDFS-5900. Cannot set cache pool limit of "unlimited" via CacheAdmin.
+    (wang)
+
 Release 2.3.0 - UNRELEASED
 
   INCOMPATIBLE CHANGES
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/tools/CacheAdmin.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/tools/CacheAdmin.java
index 290e60087f..b674d09d50 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/tools/CacheAdmin.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/tools/CacheAdmin.java
@@ -140,6 +140,18 @@ private static Long parseTtlString(String maxTtlString) throws IOException {
     return maxTtl;
   }
 
+  private static Long parseLimitString(String limitString) {
+    Long limit = null;
+    if (limitString != null) {
+      if (limitString.equalsIgnoreCase("unlimited")) {
+        limit = CachePoolInfo.LIMIT_UNLIMITED;
+      } else {
+        limit = Long.parseLong(limitString);
+      }
+    }
+    return limit;
+  }
+
   private static Expiration parseExpirationString(String ttlString)
       throws IOException {
     Expiration ex = null;
@@ -650,8 +662,8 @@ public int run(Configuration conf, List<String> args) throws IOException {
         info.setMode(new FsPermission(mode));
       }
       String limitString = StringUtils.popOptionWithArgument("-limit", args);
-      if (limitString != null) {
-        long limit = Long.parseLong(limitString);
+      Long limit = parseLimitString(limitString);
+      if (limit != null) {
         info.setLimit(limit);
       }
       String maxTtlString = StringUtils.popOptionWithArgument("-maxTtl", args);
@@ -726,8 +738,7 @@ public int run(Configuration conf, List<String> args) throws IOException {
       Integer mode = (modeString == null) ?
           null : Integer.parseInt(modeString, 8);
       String limitString = StringUtils.popOptionWithArgument("-limit", args);
-      Long limit = (limitString == null) ?
-          null : Long.parseLong(limitString);
+      Long limit = parseLimitString(limitString);
       String maxTtlString = StringUtils.popOptionWithArgument("-maxTtl", args);
       Long maxTtl = null;
       try {
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/resources/testCacheAdminConf.xml b/hadoop-hdfs-project/hadoop-hdfs/src/test/resources/testCacheAdminConf.xml
index 64de6bf87c..13f1b9ae14 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/test/resources/testCacheAdminConf.xml
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/resources/testCacheAdminConf.xml
@@ -469,6 +469,8 @@
       </test-commands>
       <cleanup-commands>
         <cache-admin-command>-removePool pool1</cache-admin-command>
+        <cache-admin-command>-removePool pool2</cache-admin-command>
+        <cache-admin-command>-removePool pool3</cache-admin-command>
       </cleanup-commands>
       <comparators>
         <comparator>
@@ -489,5 +491,33 @@
         </comparator>
       </comparators>
     </test>
+
+    <test> <!--Tested -->
+      <description>Testing setting pool unlimited limits</description>
+      <test-commands>
+        <cache-admin-command>-addPool pool1 -limit unlimited -owner andrew -group andrew</cache-admin-command>
+        <cache-admin-command>-addPool pool2 -limit 10 -owner andrew -group andrew</cache-admin-command>
+        <cache-admin-command>-modifyPool pool2 -limit unlimited</cache-admin-command>
+        <cache-admin-command>-listPools</cache-admin-command>
+      </test-commands>
+      <cleanup-commands>
+        <cache-admin-command>-removePool pool1</cache-admin-command>
+        <cache-admin-command>-removePool pool2</cache-admin-command>
+      </cleanup-commands>
+      <comparators>
+        <comparator>
+          <type>SubstringComparator</type>
+          <expected-output>Found 2 results</expected-output>
+        </comparator>
+        <comparator>
+          <type>SubstringComparator</type>
+          <expected-output>pool1  andrew  andrew  rwxr-xr-x   unlimited   never</expected-output>
+        </comparator>
+        <comparator>
+          <type>SubstringComparator</type>
+          <expected-output>pool2  andrew  andrew  rwxr-xr-x   unlimited   never</expected-output>
+        </comparator>
+      </comparators>
+    </test>
   </tests>
 </configuration>