Abstract: A power plug with leakage current protection device, which includes a body formed of an upper cover and a base, a core assembly disposed in the body, a cable assembly attached to the body, a plurality of input insertion plates and output moving contact arms which are assembled with the core assembly, and an insertion plate sleeve disposed on the base, where the input insertion plates pass through the insertion plate sleeve to protrude from the base. The insertion plate sleeve is made of an insulating and temperature resistant material. The power plug has a simple overall structure and can be assembled easily and reliably. It can prevent the safety risk caused by high temperature of the input insertion plates without increasing the size of the plug. It also has low cost, and can be suitably employed in various types of power plugs.