diff --git a/CHANGELOG.md b/CHANGELOG.md
index 110ac6c..8c8b37e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,6 +10,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Added
 
 ### Fixed
+- NDMF native strings don't fall back to en-US properly (#115)
 
 ### Changed
 
diff --git a/Editor/UI/Localization/NDMFLocales.cs b/Editor/UI/Localization/NDMFLocales.cs
index 28ec010..c08b9dc 100644
--- a/Editor/UI/Localization/NDMFLocales.cs
+++ b/Editor/UI/Localization/NDMFLocales.cs
@@ -7,7 +7,7 @@ namespace nadena.dev.ndmf.localization
     internal static class NDMFLocales
     {
         public static Localizer L = new Localizer(
-            "en-us",
+            "en-US",
             () => new List<LocalizationAsset>()
             {
                 AssetDatabase.LoadAssetAtPath<LocalizationAsset>(