The principles and development of airborne LiDAR underwater detection are described，including the principle of LiDAR underwater detection and the development history of LiDAR underwater detection. A detailed analysis of the main airborne LiDAR underwater detection systems is conducted，including mainstream airborne LiDAR depth measurement systems and their development trends. In terms of key technologies for shallow water small target detection，high-power density laser technology，high-performance underwater optical systems，wide-field rapid imaging technology，small target autonomous identification and precise positioning technology，and lightweight technology are analyzed and summarized. This serves as a reference and basis for further promoting the development of high-precision underwater target detection technology using LiDAR.