A magnetic drive sealless pump. The pump includes a casing having a fluid suction opening and fluid discharge opening. A shell is combined to the rear part of the casing, and the exterior of the shell is combined with a bracket having a motor for impelling and rotating a drive magnet. At the center of the shell is provided with a shaft enveloped with a bearing having a spiral fluid passage at the interior thereof. A capsule is provided between the bearing and the shell and at the interior of the capsule is provided with a driven magnet situated between the bearing and the drive magnet. The capsule is also extended into the casing and at the front of the capsule is provided with impeller. The impeller, capsule and bearing are integrated into one body for forming a rotating member having a thrust ring at the front and rear parts thereof, respectively, for preventing axial movements of the rotating member. Between the bearing and the capsule is an auxiliary circulating channel for cooling that has a convection effect for cooling at both the interior and exterior of the bearing without increasing the fluid leakage thereof, thereby preventing high temperatures from dry running of the pump.