A multi-channel time interval parallel measuring method based on FPGA is designed on the basis of the principle of delay line interpolation. This method can be used to solve the parallel measuring problem of a multi-channel lidar with up to 52 channels. The system in this paper mainly consists of a pulse shaping circuit, a measuring circuit and a data processing module etc. The experimental results show that the average variance of each channel is in the range 59.55 ps to 70.66 ps. The uniformity of each channel's average value is 446.8 ps. The consistency error is small. Because of the advantages of stability, high precision, small volume and easy use, the system can provide technical basis for the wide application of high precision multi-channel information acquisition technology in airborne multi-beam lidars.