The invention discloses an auxiliary heating circulating device of a solar water heater. The auxiliary heating circulating device is characterized in that a shell, a heat preservation layer and an inner container are included; an electric heating material is wound around the outer wall of the inner container of a water tank, and a temperature control probe is arranged on the outer wall of the inner container of the water tank; a heat isolating material is arranged between the electric heating material and the heat preservation layer; and a water baffle is arranged on a water outlet of a waterinlet pipe, a water tank auxiliary heating circulating pipe is arranged below an electric heating circulator, and a normally-closed solenoid valve is arranged on the auxiliary heating circulating pipe. The auxiliary heating circulating device achieves heating and heat preservation, is simple in structure, reasonable in design, convenient to use and practical, no backflow pipe needs to be mounted,water fee can be saved, and the service life is long.