Image measurement, as a noncontact pose-measurement technology, has been widely applied in various space exploration and measurement tasks in the aerospace industry. It captures spatial targets through visual imaging devices, combines the three-dimensional (3D) spatial features of the targets and their two-dimensional projections in the image, and calculates the pose parameters of the targets. This paper introduces the current development status of a rocket-borne image-measurement device and summarizes the problems it encounters and the corresponding solutions. Based on two specific applications, namely the separation of the rocket body and the measurement of the rocket-nozzle attitude, the principles and development of key technologies for rocket-borne image measurement in the aerospace field are summarized. Finally, based on the current research status and key technology analysis, the main challenges of rocket-borne image-measurement technology are discussed and recommendations for future development are provided.