The invention relates to heaters and discloses an external heating heater for a pump. The external heating heater comprises a pump casing and an electric heating pipe, wherein the pump casing is provided with a support plate with thermal conductivity; a heat transfer plate is connected to the external surface of the support plate in a thermal conduction way; a heating cavity extending along the extension direction of the electric heating pipe is formed between the heat transfer plate and the support plate; the electric heating pipe is located in the heating cavity; the electric heating pipe and the heating cavity are connected in a thermal conduction way. According to the external heating heater for the pump, the electric heating pipe is mounted at the external part of the pump casing, the utilization rate of heat produced by the electric heating pipe is high, and the problems that the electric heating pipe of the existing heating pump is short in service life, water quality is polluted after corrosion, and the maintenance is not convenient are solved.