diff --git a/tiny_gltf.h b/tiny_gltf.h
index 3572388..5d1407f 100644
--- a/tiny_gltf.h
+++ b/tiny_gltf.h
@@ -200,7 +200,11 @@ namespace tinygltf {
 
 #ifdef __ANDROID__
 #ifdef TINYGLTF_ANDROID_LOAD_FROM_ASSETS
+#ifdef TINYGLTF_IMPLEMENTATION
 AAssetManager *asset_manager = nullptr;
+#else
+extern AAssetManager *asset_manager;
+#endif
 #endif
 #endif