diff --git a/core/src/main/scala/org/apache/spark/SparkContext.scala b/core/src/main/scala/org/apache/spark/SparkContext.scala
index 566472e597958..1cd37036f9171 100644
--- a/core/src/main/scala/org/apache/spark/SparkContext.scala
+++ b/core/src/main/scala/org/apache/spark/SparkContext.scala
@@ -155,8 +155,14 @@ class SparkContext(
     new MetadataCleaner(MetadataCleanerType.SPARK_CONTEXT, this.cleanup, conf)
 
   // Initialize the Spark UI
-  private[spark] val ui = new SparkUI(this)
-  ui.bind()
+  private[spark] val ui: Option[SparkUI] =
+    if (conf.getBoolean("spark.ui.enabled", true)) {
+      Some(new SparkUI(this))
+    } else {
+      // For tests, do not enable the UI
+      None
+    }
+  ui.foreach(_.bind())
 
   val startTime = System.currentTimeMillis()
 
@@ -202,7 +208,7 @@ class SparkContext(
   @volatile private[spark] var dagScheduler = new DAGScheduler(taskScheduler)
   dagScheduler.start()
 
-  ui.start()
+  ui.foreach(_.start())
 
   /** A default Hadoop Configuration for the Hadoop code (e.g. file systems) that we reuse. */
   val hadoopConfiguration = {
@@ -777,7 +783,7 @@ class SparkContext(
 
   /** Shut down the SparkContext. */
   def stop() {
-    ui.stop()
+    ui.foreach(_.stop())
     // Do this only if not stopped already - best case effort.
     // prevent NPE if stopped more than once.
     val dagSchedulerCopy = dagScheduler
diff --git a/core/src/main/scala/org/apache/spark/scheduler/cluster/SimrSchedulerBackend.scala b/core/src/main/scala/org/apache/spark/scheduler/cluster/SimrSchedulerBackend.scala
index d99c76117c168..149c9fd1efbaa 100644
--- a/core/src/main/scala/org/apache/spark/scheduler/cluster/SimrSchedulerBackend.scala
+++ b/core/src/main/scala/org/apache/spark/scheduler/cluster/SimrSchedulerBackend.scala
@@ -44,16 +44,17 @@ private[spark] class SimrSchedulerBackend(
 
     val conf = new Configuration()
     val fs = FileSystem.get(conf)
+    val appUIAddress = sc.ui.map(_.appUIAddress).getOrElse("")
 
     logInfo("Writing to HDFS file: "  + driverFilePath)
     logInfo("Writing Akka address: "  + driverUrl)
-    logInfo("Writing Spark UI Address: " + sc.ui.appUIAddress)
+    logInfo("Writing Spark UI Address: " + appUIAddress)
 
     // Create temporary file to prevent race condition where executors get empty driverUrl file
     val temp = fs.create(tmpPath, true)
     temp.writeUTF(driverUrl)
     temp.writeInt(maxCores)
-    temp.writeUTF(sc.ui.appUIAddress)
+    temp.writeUTF(appUIAddress)
     temp.close()
 
     // "Atomic" rename
diff --git a/core/src/main/scala/org/apache/spark/scheduler/cluster/SparkDeploySchedulerBackend.scala b/core/src/main/scala/org/apache/spark/scheduler/cluster/SparkDeploySchedulerBackend.scala
index faa6e1ebe886f..dfcb22ae131dc 100644
--- a/core/src/main/scala/org/apache/spark/scheduler/cluster/SparkDeploySchedulerBackend.scala
+++ b/core/src/main/scala/org/apache/spark/scheduler/cluster/SparkDeploySchedulerBackend.scala
@@ -51,8 +51,9 @@ private[spark] class SparkDeploySchedulerBackend(
     val command = Command(
       "org.apache.spark.executor.CoarseGrainedExecutorBackend", args, sc.executorEnvs)
     val sparkHome = sc.getSparkHome().getOrElse(null)
-    val appDesc = new ApplicationDescription(appName, maxCores, sc.executorMemory, command, sparkHome,
-        "http://" + sc.ui.appUIAddress)
+    val appUIAddress = sc.ui.map { x => "http://" + x.appUIAddress }.getOrElse("")
+    val appDesc = new ApplicationDescription(
+      appName, maxCores, sc.executorMemory, command, sparkHome, appUIAddress)
 
     client = new AppClient(sc.env.actorSystem, masters, appDesc, this, conf)
     client.start()
diff --git a/pom.xml b/pom.xml
index e3f4893f70723..6a12a4ecc0b15 100644
--- a/pom.xml
+++ b/pom.xml
@@ -636,6 +636,10 @@
             <filereports>${project.build.directory}/SparkTestSuite.txt</filereports>
             <argLine>-Xms64m -Xmx3g</argLine>
             <stderr />
+            <systemProperties>
+              <spark.testing>true</spark.testing>
+              <spark.ui.enabled>false</spark.ui.enabled>
+            </systemProperties>
           </configuration>
           <executions>
             <execution>
diff --git a/project/SparkBuild.scala b/project/SparkBuild.scala
index 05b430afcec8f..2c8ee00143f0f 100644
--- a/project/SparkBuild.scala
+++ b/project/SparkBuild.scala
@@ -149,6 +149,7 @@ object SparkBuild extends Build {
     fork := true,
     javaOptions in Test += "-Dspark.home=" + sparkHome,
     javaOptions in Test += "-Dspark.testing=1",
+    javaOptions in Test += "-Dspark.ui.enabled=false",
     javaOptions += "-Xmx3g",
     // Show full stack trace and duration in test cases.
     testOptions in Test += Tests.Argument("-oDF"),
diff --git a/yarn/alpha/src/main/scala/org/apache/spark/deploy/yarn/ApplicationMaster.scala b/yarn/alpha/src/main/scala/org/apache/spark/deploy/yarn/ApplicationMaster.scala
index 66bcaf1deed3a..b4c06fa0538a7 100644
--- a/yarn/alpha/src/main/scala/org/apache/spark/deploy/yarn/ApplicationMaster.scala
+++ b/yarn/alpha/src/main/scala/org/apache/spark/deploy/yarn/ApplicationMaster.scala
@@ -227,7 +227,7 @@ class ApplicationMaster(args: ApplicationMasterArguments, conf: Configuration,
         assert(sparkContext != null || count >= numTries)
 
         if (null != sparkContext) {
-          uiAddress = sparkContext.ui.appUIAddress
+          uiAddress = sparkContext.ui.map(_.appUIAddress).getOrElse("")
           this.yarnAllocator = YarnAllocationHandler.newAllocator(
             yarnConf,
             resourceManager,
diff --git a/yarn/stable/src/main/scala/org/apache/spark/deploy/yarn/ApplicationMaster.scala b/yarn/stable/src/main/scala/org/apache/spark/deploy/yarn/ApplicationMaster.scala
index 83f8234746290..0cb347460469b 100644
--- a/yarn/stable/src/main/scala/org/apache/spark/deploy/yarn/ApplicationMaster.scala
+++ b/yarn/stable/src/main/scala/org/apache/spark/deploy/yarn/ApplicationMaster.scala
@@ -199,7 +199,7 @@ class ApplicationMaster(args: ApplicationMasterArguments, conf: Configuration,
         assert(sparkContext != null || numTries >= maxNumTries)
 
         if (sparkContext != null) {
-          uiAddress = sparkContext.ui.appUIAddress
+          uiAddress = sparkContext.ui.map(_.appUIAddress).getOrElse("")
           this.yarnAllocator = YarnAllocationHandler.newAllocator(
             yarnConf,
             amClient,