A temporary protective cover for an electrical box having an open front end includes a plate sized and shaped to be removably mounted onto the open front end of the electrical box and a pair of wings formed onto the plate for securing the cover onto the electrical box. A line of weakness extends across the rear surface of the plate from the right side edge to the left side edge. A plurality of pins are formed onto the rear surface of the plate and serve to limit longitudinal and lateral movement of the cover when mounted onto the electrical box. The pair of wings are spaced adequately in from the left and right side edges of the plate and extend rearwardly from the rear surface of the plate at an angle away from one another. Each wing is shaped to include a flexible leg and an enlarged foot, the foot including a tapered guiding surface and a substantially flat engagement surface. In other versions of the invention, the protective cover comprises a plate sized and shaped to be removably mounted onto a plaster ring which is mounted onto the electric box rather than on the electric box itself.