To provide a keeper tray corresponding to the removable keeper for easily casting a root cap by a lost wax method. The root cap is capable of attaching a conventional shaped keeper without losing magnetic attractive force, does not damage an edge of a space in which the keeper is inserted and adherently fixed when the keeper is removed at a time of MRI diagnosis, and is capable of detaching the keeper and attaching the keeper after the diagnosis.The keeper tray corresponding to the removable keeper is used at a time of casting a root cap for a dental magnetic attachment having a space S, in which the keeper is inserted and adherently fixed, by a lost wax method. The keeper tray corresponding to the removable keeper is made of a synthetic resin or a metal and has the formed space S thereon. The keeper tray corresponding to the removable keeper has a shape in which an opening 2 is formed on the bottom surface 1 by cutting out from an outer peripheral portion 1 a of the bottom surface 1 to a center portion and opens to a space S.
