Owing to the strong public concerns about environmental protection and potential energy crisis (fossil fuels), there is a global trend of substitution of petrochemical-based polymers towards biopolymers. Polybutylene succinate (PBS), as an emerging biobased and biodegradable polymer, has drawn a great deal of interest in a number of fields. However, high flammability of PBS constitutes a major obstacle for its potential application. In this study, based on the available literature, the approaches used for the flame retardancy of PBS are systematically reviewed. Those approaches include inorganic (nano)particles, lignin, and intumescent flame retardant systems. This comprehensive review aims to outline the recent research advances in the field of flame retardancy of PBS, focusing on the preparation, properties, and mechanisms. Finally, a brief summary and perspective in flame retarding PBS is also given, which may be able to inspire the development of future research and application.