To investigate the difference of mechanical properties between sleeve grouting butt joints and lap joints, 24 butt joints and 12 lap joints were tested under unidirectional tension. The failure modes, bearing loading capacity, ductility, force-displacement curves, and sleeve strain of the joints were compared and studied. During the loading process, the grouting material of the butt joints cracked in full section at the middle of the sleeve, and was pulled out of the sleeve at the end of the loading process, while the lap joint had no such situation. Test results show that the bearing loading capacity, total elongation, and stiffness of lap joint were 5-7 times, 3-5 times, and 2-3 times larger than those of butt joint respectively when the sleeve length was the same, and the displacement ductility coefficient was larger than that of butt joint. When the anchorage length was the same, the bearing capacity and displacement ductility of lap joint were slightly larger than those of butt joint. The initial stiffness difference between the joints was not obvious, but the mid-late stiffness of lap joint was higher than that of butt joint. When the middle section of the butt joint sleeve was longitudinally tensioned, the lap joint was tensioned in the early stage of loading and compressed in the late stage of loading, which reflects the lower requirement of the tensile strength of the lap joint sleeve. When the middle section of the butt joint sleeve was circumferentially compressed, the lap joint was compressed in the early stage of loading and tensioned in the late stage of loading, indicating that the restraint effect of the middle part of lap joint sleeve on the grouting material was greater than that of butt joint. The mechanical property of lap joint is better than that of butt joint, so it can be used to connect reinforcement bars in prefabricated assembly structures.