When H-shaped steel beams are connected to box columns, it can be considered that bending moment capacities of beam webs are reduced, because the out-of-plane stiffnes of the column flange in a joint panel decreases as the width-to-thikness ratio of the column flange increases. On the other hand, the presence of scallops at a beam web brings partial loss of cross section at a beam end, and the beams with scallops might reach failure at an early stage. In this study, three-point bending tests using cross-shaped specimens of beam-to-column connections are performed, and finit element method analysis are carried out. The effect of beam scallops and the width-to-thikness ratio of the flange in a joint panel on mechanical behaiviors of the steel beam end are investigated.