The coupling between solar light radiation and laser rod medium in a solar pumped laser affects the efficiency of the laser. To optimize the pumping system, simulation of the two-stage pumping system with a Fresnel lens and a conic pumping cavity is carried out with Tracepro software. According to the power density distribution along the axis at focal place of the Fresnel lens, the diameter and position of the pumping cavity window and the distance of the window from the Fresnel lens are optimized. The power density distributions along the laser rod axis of different cavity lengths and different cavity tapers are also analyzed. The optimal structure of taper cavity is obtained. The mirror reflecting cavity and ceramic cavity are introduced in detail.