This invention is a children''s toilet seat and a cover for standard toilet seats. It is conventionally attached to a standard toilet seat and comprises a rearwardly positioned, Ushaped elevated section, a forwardly positioned, depressed section having a child-sized opening therein, and an auxiliary cover which substantially conforms to the shape of the depressed section and which is pivotally mounted behind the child-sized opening for closure thereover so that the top surface of the cover of this invention is substantially planar. The auxiliary cover is provided with a brace which is pivotally attached at one end thereto and which normally rests in a recess therein. The free end of the brace travels within an aligned guide recess in the U-shaped section when the auxiliary cover is raised to support the auxiliary cover to thereby provide a backrest for a child. Retractable straps for holding a child in position and a deformable, resilient splash guard are also provided.