diff --git a/README.md b/README.md
index 01ef851f34b6f67a0de4caa3ec6cae3b91735203..f6e7f51091314a516dfacc8361f446e7e4c45e1a 100644
--- a/README.md
+++ b/README.md
@@ -81,7 +81,7 @@ versions without YARN, use:
     $ sbt/sbt -Dhadoop.version=2.0.0-mr1-cdh4.2.0 assembly
 
 For Apache Hadoop 2.2.X, 2.1.X, 2.0.X, 0.23.x, Cloudera CDH MRv2, and other Hadoop versions
-with YARN, also set `SPARK_YARN=true`:
+with YARN, also set `-Pyarn`:
 
     # Apache Hadoop 2.0.5-alpha
     $ sbt/sbt -Dhadoop.version=2.0.5-alpha -Pyarn assembly