With the composition and task form of spacecraft becoming more and more complex, more and more spacecraft were equipped with micro camera to realize visual telemetry of key objectives and their acting process in orbit. A three-dimension directed perception model based on rectangle view of micro camera was proposed for the view coverage problem of micro camera on spacecraft in this article, where pitch angle，yaw angle and roll angle of view could be adjusted to change sensing direction and view coverage area of camera. The criterion for spatial point coverage was established simultaneously. Then, genetic algorithm was used to optimize the installation site of cameras and pitch angle，yaw angle and roll angle of their view in order to achieve the coverage enhancement of the target motion space area. The proposed method was applied to optimize view coverage of lunar surface sampling space area. Computer simulating results show an effective performance of the proposed method for improving coverage ratio by view of micro camera.