In order to investigate flexural behaviors of the bolted ball-cylinder（BBC） joint，based on 2 tests on joints under one-way bending moment，finite element （FE） model was developed in ABAQUS. Failure modes，bolt internal forces as well as the load-displacement curves of the joints were obtained. By comparison，it was found that the numerical results agreed well with the experimental results，verifying the reliability of the FE model. Subsequently，joint model under bending moment was simplified and the mechanical behaviors of joint under positive and negative moments were discussed. In the parametric study，46 FE models were established to investigate the effects of different parameters on flexural behaviors of the BBC joint. The results indicate that increasing the diameter and thickness of the hollow cylinder can improve the flexural behavior of the BBC joint significantly; while the bearing capacity and stiffness of the BBC joint increase with the increase of rectangular tube width，washer thickness，size and interval of the bolts，and the effects will be more obvious when positive moment is applied to the joint. Besides，the ribbed stiffness can improve flexural behavior of the BBC joint greatly.