A portable belt sander having a drive pulley capable of being produced at a limited period. The sander includes a main body accommodating therein a motor, a drive shaft rotationally driven by the motor, a drive pulley coupled to the drive shaft, a driven shaft, and an endless polishing belt mounted between the drive pulley and the driven pulley. The drive pulley includes a base section coupling the drive shaft and made from a rigid material, and an outer low hardness section made from an elastomer material and disposed over an outer peripheral surface of the base section and integrally therewith by injection molding. Mating surfaces between the base section and the outer section are irregularly formed.