The status of ocean remote sensing is becoming more and more important. There are all kinds of resources in ocean and many ships on the sea. It is necessary for people to detect or observe these objects to know more about the natural resources and to ensure safety of ships. The paper concentrated on a compact design of a small space camera. An oscillating mirror was designed in the camera for a small volume. After that, structure analysis was done by traditional method and reduced method. The key step of reduced method was to get the reduced model. The analysis result showed that the reduced method could not only cut down the cost of computing, but also give a result with good accuracy. Besides, the analysis result indicated that the small space camera could undergo the strict load cases smoothly. The design in this paper may give some guidance to other designers and engineers when they are going to make a small space camera for ocean remote sensing.