Abstract: When the traditional up-trans photoelectric scout devices search and scout the surface targets in full field, the sky background radiation and the surface reflection yawp hold absolutely a majority of the image area, so the false alarm rate is rather high. At the same time, picking-up and scouting the surface target in complete image require exorbitant hardware and software of the video tracker. Aiming at the problems above, we proposed a control method of scout wave gate collocation strategy for fitting the up-rans photoelectric scout device. We built the math model of the virtual sea level reflected and projected by the space model of up-trans photoelectric scout device, calculated the points of intersection of the virtual sea-horizon and video image sidelines and sent to the video tracker in time, then collocated the narrowband scout wave gate along the virtual sea-horizon, the device only responded the surface target in the scouting wave gate as a result. The sea experiment result show that, the efficiency of object searching is inversely proportional to the proportion of narrowband scout in the image, and the error alarm rate reduces 80%.