This paper presents an analysis of buckling of simply supported rectangular plates reinforced by any number of transverse stiffeners and subjected to shearing forces uniformly distributed along the edges. Two cases are considered: (a) The case of a plate with a finite length; (b) one in which the length is infinite. The critical shearing stresses in both cases are expressed in similar forms, that is, τ cr d 2 E p t 2 = - π 4 384 ( 1 - ν 2 ) d r b Ω in Equation (13), and τ cr d 2 E p t 2 = π 2 24 ( 1 - ν 2 ) K in Equation (24), respectively. Design curves are drawn as shown in Figs. 2, 3, and 5.