The detection effect of laser active detection system is affected by various kinds of factors. In view of the application requirement of laser active detection, the influence factors of laser active detection were analyzed. The mathematical model of cat-eye target detection distance was built and the effect of the parameters of both the detecting system and the environment on the detection distance were analyzed. The results show that the detection distance is affected by the laser divergence angle, the incident angle and the visibility of the atmosphere. For a given detection range, smaller laser divergence angle and better visibility are benefit for enlarging the detection distance. Therefore, in view of specific application environment, it is necessary to select appropriate laser detection parameters to achieve optimal detection effect.