AbstractIn order to solve the problem of unstable detection and low detection ability of traditional photoelectric detection target in complex environment, a design method of laser photoelectric detection sensor is proposed. Laser photoelectric detection sensor with active and passive laser detection screen is formed by adding line laser to the traditional photoelectric detection target. According to the characteristics of laser echo energy when the projectile passing through the laser detection screen, the calculation model of the laser echo power received by the photoelectric detector under the random intersection of projectile and target is established, and the signal‐to‐noise ratio calculation function of the system is derived. Through the comparative test, the results show that the detection ability of the laser photoelectric detection sensor is obviously better than that of the traditional photoelectric detection target, especially in the low illumination environment; moreover, the signal‐to‐noise ratio of the laser photoelectric detection sensor still follows the law of decreasing with the increase of detection distance, and it keeps the detection characteristics of photoelectric detection system. By increasing the laser emission power, the signal‐to‐noise ratio of the laser photoelectric detection sensor is improved to a certain extent, and the detection ability of the system is improved. The results verify that the design method and theoretical model of photoelectric detection sensor proposed in this paper are scientific and feasible.