Power supply cover box

An outlet cover comprising an outlet surface and a cord container for convenient cord storage is provided. The outlet surface has at least one outlet opening, and the cord container is disposed corresponding to the outlet opening. The above cord container has a plurality of cord entry/exit holes and at least one passage connecting the plurality of cord entry/exit holes. A power supply cover box comprising a body and at least a cord container is also provided. The body includes a first end having at least one outlet opening. The cord container of the power supply cover box has a plurality of cord entry/exit holes and passages connecting the plurality of cord entry/exit holes. The passages have a predetermined width, which is preferably slightly smaller than the diameter of a regular electric cord, to retain the cord within the cord container. The cord container only allows the cord to enter or exit through the cord entry/exit holes.