In order to improve the search range and imaging resolution of the ground target by the laser tracker, a method of searching and tracking the target with a common aperture laser tracker under an airborne platform was presented and the optical system was designed. The laser tracker was fixed on the aircraft by strap down, its stability was improved. The R-C reflection telescopic system with common aperture was adopted to emit the laser and receive laser echoes, which reduced the overall size and improved the imaging resolution. The scanning search target was realized by double optical wedge component, and the search frequency was increased and the search field of view was enlarged. The relationship between the rotation angle of double optical wedge and the angle of outgoing optical deflection was given. The design results show that when the aperture of the system is φ300 mm and the focal length is 2 100 mm, the overall size is 685 mm, the search and scan field of view is ±5°, the imaging field is ±0.08°, the maximum size of the imaging spot speckle is 2.417 μm, and the MTF value of the system is greater than 0.4 at 50 lines per millimeter, which meets the imaging requirements. When the target distance is 3 km, the searchable range reaches 526 m, and the four-meter-sized target can be recognized with a imaging resolution of two seconds.