The power improvement of semiconductor lasers is of great significance to several fields, including those of national security, laser communication, laser detection/sensing, laser lighting, medical treatment. As the semiconductor laser beam combining technology can considerably improve the output power while ensuring the beam quality, it has attracted wide attention in recent years. Spectral beam combining (SBC) and coherent beam combining (CBC) are two typical semiconductor beam combining technologies, and many institutions have made breakthroughs in relevant research. In this paper, the development of these semiconductor laser beam combining technologies is reviewed and their prospect is discussed.