Abstract: The elastic stability of bars is analyzed through considering the effect of the shear deformations. The influences of the bars’ shear deformations to their critical loads are mainly discussed. The first and second order slope displacement equations for the beam element are proposed, where the effect of shear deformations are taken into account. The simple formulae for the sway and non-sway buckling critical loads of the bars, which has arbitrary rotational restraints at both ends, are proposed respectively. Comparing with the accurate solutions, the proposed formulae have excellent accuracy. The internal relationships between the bars’ sway buckling critical loads with their lateral stiffness have been concluded, and according to the relationship, the simple formula for the critical load of the bar with insufficient lateral support has been proposed.