The stray light characteristics of different catadioptric ground-based photoelectric detection system were analyzed. The relevant stray light suppression ways were discussed. Based on structure with middle image surface and the other one without middle image surface, two different suppression schemes for the stray light were provided respectively. Besides, the thermal radiation for the long wave infrared system was analyzed. The results show that adding out baffle to the catadioptric system without middle image surface can do well obviously in reducing stray light with large off-axis angles. However, adding stops and the inner baffle of primary mirror to the catadioptric system with middle image surface can reduce the outer stray light obviously. This can reduce the length and weight greatly. If the thermal radiation demand can be satisfied, the miniaturization and lightweight design had been realized.