diff --git a/azkaban-common/src/main/java/azkaban/project/DirectoryYamlFlowLoader.java b/azkaban-common/src/main/java/azkaban/project/DirectoryYamlFlowLoader.java
index 858b6ee..71599cb 100644
--- a/azkaban-common/src/main/java/azkaban/project/DirectoryYamlFlowLoader.java
+++ b/azkaban-common/src/main/java/azkaban/project/DirectoryYamlFlowLoader.java
@@ -139,7 +139,9 @@ public class DirectoryYamlFlowLoader implements FlowLoader {
// Add edges for the flow.
buildFlowEdges(azkabanFlow, flowName);
- flow.addAllEdges(this.edgeMap.get(flowName));
+ if (this.edgeMap.containsKey(flowName)) {
+ flow.addAllEdges(this.edgeMap.get(flowName));
+ }
// Todo jamiesjc: deprecate startNodes, endNodes and numLevels, and remove below method finally.
// Blow method will construct startNodes, endNodes and numLevels for the flow.
