At present,all-fiber coherent Doppler lidar mostly uses acousto-optic modulator (AOM) to modulate frequency of reference light.A kind of new all-fiber coherent Doppler lidar with no acousto-optic modulator was proposed.First,the signal processing used in this system was used to measure the simulated Doppler shift.The simulation results indicate that the more noise is added to the signal,the more errors will be obtained from the calculation. Then the lidar system was utilized to measure the velocity of atmosphere produced by a fan.The results conform very closely to the reference ,whose absolute errors are less than 0.15m/s. The simulation and experient results validate the accuracy of the lidar system.