Abstract: In this paper, according to the simplified theory of [1], the bending of rectangular plates with two opposite edges simply supported and other two opposite edges being arbitrary under the action of a concentrated load is treated by means of properties of two-variable-function and the method of series, The effect of transverse shearing forces on the bending of plates is considered. When the thickness h of plates is small, and the term, whose orders are more than order of h² are neglected, then the results agree with the solutions corresponding to the problem of thin plates, At the end, the solutions of the bending problem of plates with arbitrary linear distributed load are also obtained.