diff --git a/HMCL/src/main/java/org/jackhuang/hmcl/ui/versions/Versions.java b/HMCL/src/main/java/org/jackhuang/hmcl/ui/versions/Versions.java
index 5c4ce50ba7..1c9c79a078 100644
--- a/HMCL/src/main/java/org/jackhuang/hmcl/ui/versions/Versions.java
+++ b/HMCL/src/main/java/org/jackhuang/hmcl/ui/versions/Versions.java
@@ -264,6 +264,11 @@ public static void generateLaunchScript(Profile profile, String id, Consumer<Lau
             chooser.getExtensionFilters().add(new FileChooser.ExtensionFilter(i18n("extension.ps1"), "*.ps1"));
             Path file = FileUtils.toPath(chooser.showSaveDialog(Controllers.getStage()));
             if (file != null) {
+                if (!isValidScriptExtension(FileUtils.getExtension(file))) {
+                    String defaultExt = getDefaultScriptExtension();
+                    file = file.resolveSibling(file.getFileName().toString() + "." + defaultExt);
+                }
+
                 LauncherHelper launcherHelper = new LauncherHelper(profile, account, id);
                 for (Consumer<LauncherHelper> injecter : injecters) {
                     injecter.accept(launcherHelper);
@@ -273,6 +278,21 @@ public static void generateLaunchScript(Profile profile, String id, Consumer<Lau
         });
     }
 
+    private static boolean isValidScriptExtension(String ext) {
+        if (OperatingSystem.CURRENT_OS == OperatingSystem.WINDOWS) {
+            return ext.equalsIgnoreCase("bat") || ext.equalsIgnoreCase("ps1");
+        }
+        return ext.equalsIgnoreCase("sh") || ext.equalsIgnoreCase("bash") || ext.equalsIgnoreCase("command") || ext.equalsIgnoreCase("ps1");
+    }
+
+    private static String getDefaultScriptExtension() {
+        return switch (OperatingSystem.CURRENT_OS) {
+            case WINDOWS -> "bat";
+            case MACOS -> "command";
+            default -> "sh";
+        };
+    }
+
     @SafeVarargs
     public static void launch(Profile profile, String id, Consumer<LauncherHelper>... injecters) {
         if (!checkVersionForLaunching(profile, id))
diff --git a/HMCLCore/src/main/java/org/jackhuang/hmcl/launch/DefaultLauncher.java b/HMCLCore/src/main/java/org/jackhuang/hmcl/launch/DefaultLauncher.java
index f5896914cf..090a483e99 100644
--- a/HMCLCore/src/main/java/org/jackhuang/hmcl/launch/DefaultLauncher.java
+++ b/HMCLCore/src/main/java/org/jackhuang/hmcl/launch/DefaultLauncher.java
@@ -644,10 +644,10 @@ public void makeLaunchScript(Path scriptFile) throws IOException {
         boolean usePowerShell = "ps1".equals(scriptExtension);
 
         if (!usePowerShell) {
-            if (isWindows && !scriptExtension.equals("bat"))
+            if (isWindows && !scriptExtension.equalsIgnoreCase("bat"))
                 throw new IllegalArgumentException("The extension of " + scriptFile + " is not 'bat' or 'ps1' in Windows");
-            else if (!isWindows && !(scriptExtension.equals("sh") || scriptExtension.equals("command")))
-                throw new IllegalArgumentException("The extension of " + scriptFile + " is not 'sh', 'ps1' or 'command' in macOS/Linux");
+            else if (!isWindows && !(scriptExtension.equalsIgnoreCase("sh") || scriptExtension.equalsIgnoreCase("command") || scriptExtension.equalsIgnoreCase("bash")))
+                throw new IllegalArgumentException("The extension of " + scriptFile + " is not 'sh', 'bash', 'ps1' or 'command' in macOS/Linux");
         }
 
         final Command commandLine = generateCommandLine(nativeFolder);