In designing of bolted joints, it is important to discuss a clamping effect (contact stress distribution) and to estimate the force ratio (a ratio of a n increment of bolt axial force to an external load). In order to improve the clamping effect, raised faces of the interfaces have been used. But theoretical grounds are not made clear. Also investigations on the case where an external bending moment is applied on bolted joints are not found except any reports. In this paper, the clamping effect and the force ratio in the case where T-flanges of which interfaces have non-contacted parts are subjected to external bending moments are analyzed using two-dimensional theory of elasticity and point-matching method. For verification, experiments are carried out with respect to the contact stress distribution and the force ratio for the external bending moment. Analytical results are in a fairly good agreement with experimental ones.