Abstract: In order to improve laser range ability of the pulse laser ranging finder system with the photoelectric detecting device in navigation system, a laser echo wave receiver circuit was designed based on cooling-APD (avalanche photodiode detector). According to the characteristics of cooling-APD, the most appropriate TEC (thermo electric cooler) cooling power was output to reduce temperature on APD, thus the APD ran in best condition with not only lower noise voltage but also higher detecting sensibility. Experiments show that when incident light power is 80 W with attenuation of 45.6 dB, false alarm rate declines from 8.57% to 0.49% after cooling of APD. So applying the circuit into new airborne photoelectric detecting device, it will promote sensitivity of the receiver system, and at the same time, it will help make a great improvement on the long-distance laser range ability, which can meet the new airborne photoelectric detection system of remote distance military requirements.