Space-based 3D imaging LIDAR is an important means of space target observation.According to the imaging method,the space-based LIDAR includes continuous wave LIDAR and pulsed LIDAR,and then their imaging principles are introduced briefly.According to the application background of LIDAR,the characteristics and main parameters of LIDAR are analyzed.The common characteristics of the typical LIDAR are analyzed from the respect of the imaging principle,the angle resolution,the working distance and the development trend,which provides a reference for the design of LIDAR.Finally,it gives some suggestions on the development and application of space-based 3D imaging LIDAR based on the current situation and bottleneck of LIDAR in our country.