diff --git a/plugins/hg4idea/src/org/zmlx/hg4idea/command/HgCommitCommand.java b/plugins/hg4idea/src/org/zmlx/hg4idea/command/HgCommitCommand.java
index dfd8797301d3..ffcd31656ba2 100644
--- a/plugins/hg4idea/src/org/zmlx/hg4idea/command/HgCommitCommand.java
+++ b/plugins/hg4idea/src/org/zmlx/hg4idea/command/HgCommitCommand.java
@@ -18,8 +18,6 @@ import com.intellij.openapi.util.io.FileUtil;
 import com.intellij.openapi.util.text.StringUtil;
 import com.intellij.openapi.vcs.VcsException;
 import com.intellij.openapi.vfs.VirtualFile;
-import com.intellij.util.Function;
-import com.intellij.util.containers.ContainerUtil;
 import com.intellij.util.messages.MessageBus;
 import com.intellij.vcsUtil.VcsFileUtil;
 import org.jetbrains.annotations.NotNull;
@@ -33,7 +31,10 @@ import org.zmlx.hg4idea.util.HgUtil;
 
 import java.io.File;
 import java.io.IOException;
-import java.util.*;
+import java.util.Collections;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Set;
 
 import static org.zmlx.hg4idea.HgErrorHandler.ensureSuccess;
 
@@ -62,16 +63,23 @@ public class HgCommitCommand {
       throw new HgCommandException(HgVcsMessages.message("hg4idea.commit.error.messageEmpty"));
     }
     List<String> relativePaths = HgUtil.getRelativePathsByRepository(myFiles).get(myRoot);
+    //if it's merge commit, so myFiles is Empty. Need to commit all files in changeList, can't call setFiles() method.
+    // see HgCheckinEnviroment->commit() method
     if (relativePaths == null) {
-      return; // relativePaths for root shouldn't be empty;
-    }
-    for (List<String> chunk : VcsFileUtil.chunkRelativePaths(relativePaths)) {
       List<String> parameters = new LinkedList<String>();
       parameters.add("--logfile");
       parameters.add(saveCommitMessage().getAbsolutePath());
-      parameters.addAll(chunk);
       ensureSuccess(new HgCommandExecutor(myProject).executeInCurrentThread(myRoot, "commit", parameters));
     }
+    else {
+      for (List<String> chunk : VcsFileUtil.chunkRelativePaths(relativePaths)) {
+        List<String> parameters = new LinkedList<String>();
+        parameters.add("--logfile");
+        parameters.add(saveCommitMessage().getAbsolutePath());
+        parameters.addAll(chunk);
+        ensureSuccess(new HgCommandExecutor(myProject).executeInCurrentThread(myRoot, "commit", parameters));
+      }
+    }
     final MessageBus messageBus = myProject.getMessageBus();
     messageBus.syncPublisher(HgVcs.REMOTE_TOPIC).update(myProject, null);
     messageBus.syncPublisher(HgVcs.BRANCH_TOPIC).update(myProject, null);