Abstract: The progressive bending process parameters of AZ31 magnesium alloy grid panel were determined by experimental study, and the qualified bending parts were obtained. The influencing factors and rules of curvature radius of bending parts were analyzed. The mathematical relationship model between curvature radius of AZ31 magnesium alloy grid panel bending parts and bending die spacing and reduction height was established. The effect of progressive bending parameters on the grain size of magnesium alloy panel was analyzed.The results show that the calculation results of the model are in good agreement with the experimental results, and the maximum relative error is 5.7%. With the increase of bending deformation coefficient, the grain size decreases, and with the increase of deformation temperature, the grain size increases.