Semiconductor laser has been half a century since its birth, tremendous progress has been made in theory, practice, and applications, and the market occupies more than half of the entire laser field. It is widely used in communication networks, industrial processing, medical and beauty, laser sensing, aviation and defense, security protection, and even consumer electronics. On the basis of reviewing the development history of early domestic and international semiconductor lasers, this article mainly focuses on GaAs-based 8xx nm and 9xx nm semiconductor lasers in the field of high-power pump sources, 905 nm tunnel junction lasers and 940 nm vertical cavity surface emitting lasers in the field of three-dimensional sensing, and GaSb-based infrared lasers and InP-based quantum cascade lasers in the field of spectral analysis and infrared sensing, for a brief review. The content includes the main application scenarios, the main goals pursued, the latest developments in the past 10 years at home and abroad, and the possible development trends and directions in the future.