To improve the connection efficiency of steel structure module units, a clamp-bolted connection joint between block units was proposed. A finite element model of the joint was established to analyze the static performance, seismic performance, and the influence laws of three parameters (side wall thickness of the welded connection surface between the corner fitting and the module steel beam (side wall thickness of corner fitting), wall thickness of the positioning clamp, and wall thickness of the module steel beam) on the mechanical performance of the joint. The results show that the clamp-bolted connection joint features a simple and reasonable structure, a clear load-transfer mechanism, and favorable seismic performance; increasing the wall thickness of the module steel beam can improve the maximum bearing capacity, as well as the overall stiffness and energy dissipation capacity of the joint to a certain extent; increasing the wall thickness of the positioning clamp can improve the initial stiffness of the joint but reduces its energy dissipation capacity, and excessive wall thickness of the positioning clamp reduces the ultimate bearing capacity of the joint; increasing the side wall thickness of the corner fitting can improve the bearing capacity of the joint, and greatly enhances its energy dissipation capacity, but weakens the stiffness of the joint.