A high-speed data acquisition system based on “FPGA+DSP” for echo signal sampling of lidar was proposed. FPGA in the system samples four channels signal simultaneously, cumulates and caches it. DSP reads into data and then average them, after retrieving by a certain algorithm, then transmite to the remote PC by the protocol of TCP/IP. Satisfactory results were obtained when the data acquisition system was applied in a Mie scattering laser radar. Results show that the system can sample the echo signal repeating at 1 kHz by a frequency of 20 MHz, and it can accumulate the corresponding data more than 5000 times, which meet the special features of lidar data acquisiton. The data acquisition system is worth popularizing in the multispectral lidar and the high spectral resolution lidar for features of cost-effective, portable, and can share the data remotely.