The plate-lap connection and flange connection collaborated as hybrid bolted connection is proposed and used to assemble steel box girder, named the non-axial force connection. However, the impact of various parameters on its bending behaviour is insufficient in reference. Hence, this paper aims to evaluate the structural responses of this novel connection under the in-plane bending moment. The moment-curvature characteristic model is proposed and defined according to experimental results. Based on the validated finite element method against experimental result, parametric analysis considering the effect of material and geometrical properties is conducted to evaluate the bending behaviours, containing the elastic and yield stiffness defined in the moment-curvature characteristic model. It indicates that the material strength improvement of the main components show no influence on the elastic stiffness of steel box girder, but the increasing effect over 70% from S420 to S550 steel is captured for the yield stiffness. The increase geometrical configuration of steel box girder can both improve the elastic and yield stiffness with the maximum effect of 18% and 90% for the increase thicknesses of the top flange, respectively. However, the slight impact of the thickness of the connection plate on the yield stiffness within 5%, since it presents the elastic response as steel box girder reaching the yield strength.