Laser shock strengthening, a non-contact method with superior control and enhancement effects, offers innovative modifications to gear surfaces. By manipulating the residual stress field spread over the gear surface, this technology significantly improves gear lifespan. This study delves into the impact of laser shock strengthening on gear surface′s residual stress, exploring four crucial process parameters: laser energy, laser spot size, laser spot bonding rate, and laser shock frequency. It provides an in-depth discussion of their influence on gear′s residual stress while reviewing the merits and demerits of composite laser shock strengthening techniques currently available. The regulatory impacts of combined methods such as laser shock strengthening-shot peening, laser quenching-laser shock strengthening, ultrasonic impact peening-laser shock strengthening, and electropulsing-assisted laser shock strengthening on residual stress are also assessed. In conclusion, it summarizes research advancements concerning gear surface residual stress reinforcement by laser shock technology and forecasts future developments and applications of laser shock.