diff --git a/jvm-packages/xgboost4j-spark/src/main/scala/ml/dmlc/xgboost4j/scala/spark/XGBoost.scala b/jvm-packages/xgboost4j-spark/src/main/scala/ml/dmlc/xgboost4j/scala/spark/XGBoost.scala
index 4b4da36cb..5fcdf81e5 100644
--- a/jvm-packages/xgboost4j-spark/src/main/scala/ml/dmlc/xgboost4j/scala/spark/XGBoost.scala
+++ b/jvm-packages/xgboost4j-spark/src/main/scala/ml/dmlc/xgboost4j/scala/spark/XGBoost.scala
@@ -81,12 +81,15 @@ object XGBoost extends Serializable {
   def train(trainingData: RDD[LabeledPoint], configMap: Map[String, Any], round: Int,
       nWorkers: Int = 0, obj: ObjectiveTrait = null, eval: EvalTrait = null): XGBoostModel = {
     implicit val sc = trainingData.sparkContext
-    if (configMap.contains("nthread")) {
-      val nThread = configMap("nthread")
+    var overridedConfMap = configMap
+    if (overridedConfMap.contains("nthread")) {
+      val nThread = overridedConfMap("nthread")
       val coresPerTask = sc.getConf.get("spark.task.cpus", "1")
       require(nThread.toString <= coresPerTask,
         s"the nthread configuration ($nThread) must be no larger than " +
           s"spark.task.cpus ($coresPerTask)")
+    } else {
+      overridedConfMap = configMap + ("nthread" -> sc.getConf.get("spark.task.cpus", "1").toInt)
     }
     val numWorkers = {
       if (nWorkers > 0) {
@@ -97,7 +100,7 @@ object XGBoost extends Serializable {
     }
     val tracker = new RabitTracker(numWorkers)
     require(tracker.start(), "FAULT: Failed to start tracker")
-    val boosters = buildDistributedBoosters(trainingData, configMap,
+    val boosters = buildDistributedBoosters(trainingData, overridedConfMap,
       tracker.getWorkerEnvs.asScala, numWorkers, round, obj, eval)
     val sparkJobThread = new Thread() {
       override def run() {