Semiconductor lasers can be applied as ideal laser sources toward the development of laser and sensing technologies. For laser radar measurement, optical pumping, and fiber coupling, semiconductor lasers must have high power and high beam quality. The design of high-power semiconductor lasers promotes the easy production of multi-mode beams in the lateral direction, which decreases the lateral beam quality. Hence, the limitations induced by the lateral mode and the enhancement of the lateral beam quality of high-power semiconductor lasers have become important research topics. This paper focuses on three topics: the tapered laser, the method for the improvement of the lateral beam quality of a broad-area semiconductor laser, and the package structure of a semiconductor laser. Furthermore, the results and progress of domestic and international research on the control of the lateral beam quality are reviewed.