Abstract: A replaceable toilet tank cover is provided having a base member with a top surface and a bottom surface. A lip is defined around the sides of the cover. At least two post members are disposed on the bottom surface and are set off from the lip a predetermined distance so that a tank wall of the toilet tank can fit between the post members and the lip. A resilient retaining device is disposed on the bottom surface adjacent from and set off from the lip. The retaining device has at least two spring arms resiliently movable in a plane generally parallel to the bottom surface for resiliently pressing against the inside surface of the toilet tank wall thereby clamping the tank wall between the lip and the spring arms.