A high-precision coherent laser ranging method based on Kalman filtering is proposed using a single-linear frequency modulated continuous wave (S-LFMCW) laser as the transmitting signal . By measuring the beat frequency between the echo signal and the local oscillator signal, the frequency difference is first obtained. The distance and speed of the target are then calculated with this frequency difference signal through analog-to-digital conversion and digital signal processing. Finally, the Kalman filter algorithm is used to fuse the measured data, and the target distance estimation is obtained with high accuracy. The experimental results show that the proposed method is suitable for large-scale dynamic coherent laser ranging lidar systems. The effective ranging range of the system is 8 m to 2.7 km, and the ranging accuracy is within 0.1 m.