diff --git a/nixos/hosts/nixos-vm-01/default.nix b/nixos/hosts/nixos-vm-01/default.nix
index 855d886d..242b3e72 100644
--- a/nixos/hosts/nixos-vm-01/default.nix
+++ b/nixos/hosts/nixos-vm-01/default.nix
@@ -18,7 +18,9 @@
   time.timeZone = "Asia/Tokyo";
   networking.hostName = "nixos-vm-01";
 
-  boot.loader.enable = true;
-  boot.loader.grub.device = "/dev/sda";
-  boot.loader.grub.useOSProber = true;
+  boot.loader.grub = {
+    enable = true;
+    device = "/dev/sda";
+    useOSProber = true;
+  };
 }