A safety protection structure for universal sockets, comprising: a second module; a second slant to contact the second pin of a 3-pin plug; a sliding chute configured in parallel to the movement direction of the second module; a third module; a third slant to contact the third pin of a 3-pin plug, and matching the sliding chute of the second module. The sliding chute is configured to ensure that the third and the second module are relatively independent and movable. The second module and third module are respectively configured with a surface area to block the second pin and third pin of the 3-pin plug at the same time. In this configuration, the insulation board is closed when the pin of the plug is inserted incorrectly preventing the pin from contacting the conducting plate in the socket, and the insulation boards in the jacks not inserted with the pins remain closed.