Abstract: In order to solve for the displacement of any section of a simply supported beam more conveniently. Borrowing the idea of the displacement method, the simply supported beam is transformed into two statically indeterminate beams fixed at one end and simply supported at the other end after being cut off from the cross-section to be dislocated, and then the relationship of equal bending moments and equal shear forces is utilized to give the three ways of establishing a system of binary equations on the angular displacement of the cross-section to be dislocated and the linear displacement. Examples show that the displacement method is more convenient than other methods for solving the displacement of any cross-section of a simply supported beam, especially when the type and distribution of loads are complex, the advantages of the displacement method are more obvious.