Target pointing accuracy, as one of the core indicators of photoelectric tracking equipment, is the focus of attention in the equipment design, manufacturing and testing stages. The photoelectric tracking equipment installed on ships and other moving carriers often adds a stable platform to control the optical axis and image stabilization. Taking a photoelectric tracking and pointing device with a stable platform as an example, a kinematics-based target pointing error model is established is this paper. And based on this model, the geometric errors are assigned in detail, which can be used to guide the analysis, assembly and calibration of similar products.