The inter-satellite optical communication system consists of acquisition, pointing and tracking technology; the acquisition technology, which is the premise and guarantee for normal work. The principle of acquisition, key technology and engineering implementation under scanning stare mode were studied in detail. A method for combination of the coarse fine pointing of spiral sine was presented. Numerical simulation results for the scanning process prove that the proposed method has smaller missing scanning area, higher acquisition probability and shorter acquisition time when compared with the traditional single coarse scanning. The coarse fine scanning type is a new method for inter-satellite communication. The proposed method has an important significance in providing a new method for inter-satellite laser communication.