The invention relates to a phase recovery device based on the Ronchi raster Talbot effect and a work method thereof. The phase recovery device comprises a Ronchi raster and a high sensitivity CCD camera and is characterized in that the CCD camera is arranged at the Talbot distance of the Ronchi raster. The method comprises steps that firstly, a self image of the Ronchi raster is acquired through the CCD camera; secondly, background noise removal pre-processing on the acquired self image of the Ronchi raster is carried out; and thirdly, phase recovery is carried out, the phase information is optimized through a phase recovery algorithm for multiple times of cycle iteration, and incoming wavefront is outputted after optimization. The method are advantaged in that disadvantages of high systemcomplexity and large operation difficulty existing in a system in the prior art are overcome, phase recovery is carried out through utilizing the Talbot effect of the Ronchi raster, the recovery algorithm has good convergence, phase recovery precision is high, and relatively strong noise-immune capability is realized. The device is advantaged in that the structure is simple, and application demands in various fields such as phase measurement and wave surface analysis can be satisfied.