In order to clarify the mechanism of membrane-soil separation in the process of mechanical recovery of the residual membrane in farmland, a mathematical model of the contact model between residual membrane and soil particles and a mathematical model of the change law of binding force between residual membrane and soil particles was established based on soil contact theory and soil adhesion mechanics. The EDEM software was used to carry out the peeling shear simulation tests of the residual film with the thickness of 0.0， 0.02 and 0.03 mm. The fitting results show that there is a cubic relationship between membrane-soil separation shear force and peel shear displacement under different residual film thickness, and the determination coefficient R2 were 0.805 9, 0.872 2 and 0.878 4, respectively. The coefficients of determination R2 were 0.793 2, 0.854 8, 0.869 0 by fitting the bench verification test, respectively. It is found that the maximum relative error was 13.77%.