diff --git a/mllib/src/main/scala/org/apache/spark/mllib/fpm/PrefixSpan.scala b/mllib/src/main/scala/org/apache/spark/mllib/fpm/PrefixSpan.scala
index d5f0c926c69bb49d62bba9f4dc99fc3a1cfc1982..ad6715b52f337453fe3f07cf669ba759f9ba33f8 100644
--- a/mllib/src/main/scala/org/apache/spark/mllib/fpm/PrefixSpan.scala
+++ b/mllib/src/main/scala/org/apache/spark/mllib/fpm/PrefixSpan.scala
@@ -82,7 +82,7 @@ class PrefixSpan private (
   /**
    * Gets the maximal pattern length (i.e. the length of the longest sequential pattern to consider.
    */
-  def getMaxPatternLength: Double = maxPatternLength
+  def getMaxPatternLength: Int = maxPatternLength
 
   /**
    * Sets maximal pattern length (default: `10`).