diff --git a/nixos/tests/installer.nix b/nixos/tests/installer.nix
index 2bee2f77999f..2064675ecd94 100644
--- a/nixos/tests/installer.nix
+++ b/nixos/tests/installer.nix
@@ -449,7 +449,7 @@ in {
         "btrfs subvol create /mnt/boot",
         "btrfs subvol create /mnt/nixos",
         "umount /mnt",
-        "mount -o defaults,subvol=mnt LABEL=root /mnt",
+        "mount -o defaults,subvol=nixos LABEL=root /mnt",
         "mkdir /mnt/boot",
         "mount -o defaults,subvol=boot LABEL=root /mnt/boot",
       );