diff --git a/Tools/Source/GenBuild/org/tianocore/build/autogen/AutoGen.java b/Tools/Source/GenBuild/org/tianocore/build/autogen/AutoGen.java
index 751438c27d..fa7b8a8b90 100644
--- a/Tools/Source/GenBuild/org/tianocore/build/autogen/AutoGen.java
+++ b/Tools/Source/GenBuild/org/tianocore/build/autogen/AutoGen.java
@@ -25,6 +25,7 @@ import java.io.FileWriter;
 import java.util.ArrayList;
 import java.util.HashSet;
 import java.util.Iterator;
+import java.util.LinkedHashSet;
 import java.util.LinkedList;
 import java.util.List;
 import java.util.Map;
@@ -659,7 +660,7 @@ public class AutoGen {
 	 */
 	Set<String> LibraryClassToAutogenH(String[] libClassList)
 			throws AutoGenException {
-		Set<String> includStrList = new HashSet<String>();
+		Set<String> includStrList = new LinkedHashSet<String>();
 		String includerName[];
 		String str = "";