diff --git a/core/src/main/java/hudson/model/AbstractProject.java b/core/src/main/java/hudson/model/AbstractProject.java
index 954011f650d4..567080e6680e 100644
--- a/core/src/main/java/hudson/model/AbstractProject.java
+++ b/core/src/main/java/hudson/model/AbstractProject.java
@@ -1207,7 +1207,12 @@ public boolean checkout(AbstractBuild build, Launcher launcher, BuildListener li
             return true;    // no SCM
 
         FilePath workspace = build.getWorkspace();
-        workspace.mkdirs();
+        if(workspace!=null){
+            workspace.mkdirs();
+        } else {
+            throw new AbortException("Cannot checkout SCM, workspace is not defined");
+        }
+
 
         boolean r = scm.checkout(build, launcher, workspace, listener, changelogFile);
         if (r) {