diff --git a/modules/basic-theme/src/Volo.Abp.AspNetCore.Mvc.UI.Theme.Basic/Bundling/BasicThemeGlobalStyleContributor.cs b/modules/basic-theme/src/Volo.Abp.AspNetCore.Mvc.UI.Theme.Basic/Bundling/BasicThemeGlobalStyleContributor.cs
index 6b22d0c894..9c54affdf0 100644
--- a/modules/basic-theme/src/Volo.Abp.AspNetCore.Mvc.UI.Theme.Basic/Bundling/BasicThemeGlobalStyleContributor.cs
+++ b/modules/basic-theme/src/Volo.Abp.AspNetCore.Mvc.UI.Theme.Basic/Bundling/BasicThemeGlobalStyleContributor.cs
@@ -7,5 +7,6 @@ public class BasicThemeGlobalStyleContributor : BundleContributor
     public override void ConfigureBundle(BundleConfigurationContext context)
     {
         context.Files.Add("/themes/basic/layout.css");
+        context.Files.Add("/themes/basic/custom/select2-bs5-fix.css");
     }
 }
diff --git a/modules/basic-theme/src/Volo.Abp.AspNetCore.Mvc.UI.Theme.Basic/wwwroot/themes/basic/custom/select2-bs5-fix.css b/modules/basic-theme/src/Volo.Abp.AspNetCore.Mvc.UI.Theme.Basic/wwwroot/themes/basic/custom/select2-bs5-fix.css
new file mode 100644
index 0000000000..beb981c139
--- /dev/null
+++ b/modules/basic-theme/src/Volo.Abp.AspNetCore.Mvc.UI.Theme.Basic/wwwroot/themes/basic/custom/select2-bs5-fix.css
@@ -0,0 +1,4 @@
+/*TODO: Remove after BS5 Modal support of select2 */
+span.select2-container.select2-container--default.select2-container--open {
+    z-index: 1056; /*Just for BS5 Modals*/
+}