In order to make full use of sunlight and improve photocatalytic degradation efficiency, a new rotary solar photocatalytic reactor with focus reflector was designed. The new type of solar photocatalytic reactor we designed solves such problems as shallow optical depth, small surface area, the need for aeration and agitation, insufficient contacting time or sunlight intensity in the photocatalytic reaction. It has the characteristics of cheap price and easy operation. Using focus reflector to increase the light intensity can improve decomposing efficiency. The paper also studied the method for the immobilization of the catalyst.