Abstract: For problems of slow convergence speed and large calculation amount existed in non-linear inversion methods of mine seismic wave velocity inversion, a model space dimensionality reduction method of mine seismic wave velocity inversion was proposed based on 2D fast Fourier transformation. The method can reduce model space dimensionality of mine seismic wave velocity inversion on the premise of partial loss of high frequency information through 2D fast Fourier transformation and high frequency truncation, so as to speed up seismic wave velocity inversion. The experimental results show that model space dimensionality of 50×50 grid can be reduced to 1/100 by use of the method, and on this basis, particle swarm optimization algorithm can be used to invert the seismic wave velocity, which can converge rapidly and obtain inversion value close to the theoretical value stably.