The invention discloses an all-fiber wind measurement laser radar apparatus based on an asymmetric M-Z interferometer and a method. On one hand, an asymmetric M-Z interferometer formed by a 2*2 fiber coupler and a 3*3 fiber coupler is used as a frequency discriminator of a wind measurement laser radar; compared with Fabry-Perot interferometer, the M-Z interferometer has advantages like high transmittance and large detectable wind speed dynamic scope; compared with traditional space optical profile type M-Z interferometer, the M-Z interferometer provided by the invention has advantages like strong anti-interference capability, compact structure, stable system and convenient light modulation etc.; compared with symmetrical M-Z interferometer based on 2*2 fiber coupler, there is no need to lock the laser at the halfway point of the M-Z interferometer, therefore, the measurement sensitivity can be raised by reducing the free spectrum spacing of the M-Z interferometer; on the other hand, the demodulation method of differential intersect multiply by is adopted, and the energy injected into the MZI is normalized, therefore, the solution is not sensitive to the fluctuating of the laser energy.