Structural deformation monitoring of flight vehicles based on optical fiber sensing (OFS) technology has been a focus of research in the field of aerospace. After nearly 30 years of research and development, Chinese and international researchers have made significant advances in the areas of theory and methods, technology and systems, and ground experiments and flight tests. These advances have led to the development of OFS technology from the laboratory research stage to the engineering application stage. However, a few problems encountered in practical applications limit the wider application and further development of this technology, and thus urgently require solutions. This paper reviews the history of research on the deformation monitoring of flight vehicles. It examines various aspects of OFS-based deformation monitoring including the main varieties of OFS technology, technical advantages and disadvantages, suitability in aerospace applications, deformation reconstruction algorithms, and typical applications. This paper points out the key unresolved problems and the main evolution paradigms of engineering applications. It further discusses future development directions from the perspectives of an evolution paradigm, standardization, new materials, intelligentization, and collaboration.