The invention discloses a single-phase protection grounding switch and a grounding protection system, belong to the technical field of power distribution equipment, and especially relates to a single-phase protection grounding switch and a grounding protection system. The invention provides the single-phase protection grounding switch and the grounding protection system capable of avoiding the occurrence of single-phase earth fault from burning electrical equipment. The single-phase protection grounding switch comprises a mechanism support; one side of the mechanism support is provided with an insulator, and the upper end of the insulator is connected with a grounding fixed contact; the lower end of the other side of the mechanism support is coupled with one end of an opening-closing spring, and the other end of the opening-closing spring is coupled with one end of a grounding moving contact through a spring coupling plate; the other end of the grounding moving contact is of a clamping plate structure; the clamping plate is provided with a notch; the notch is provided with a belleville spring which is matched with the grounding fixed contact; the grounding moving contact is provided with a grounded outlet; and a part of the spring coupling plate coupled with the grounding moving contact is matched with a clamping slot at the upper rear end of an opening-closing rotating plate.