To improve the shear performance of precast assembled beams, this paper proposes a novel prefabricated beam joint, which is crucial for enhancing structural integrity and service life. The study experimentally verifies the shear performance of the novel prefabricated beam joint by testing four beams, with the steel plate cross-sectional area ratio at the joint connection as the primary parameter. An anti-symmetric loading method was adopted to position the joint within the beam's contraflexure region, where the bending moment approaches zero and the shear force remains relatively small. This configuration reduces the risk of joint failure and facilitates disassembly and replacement. The results show that: 1) The new joint maintains original internal force transmission mechanisms, ensuring effective load transfer; 2) Increased steel plate ratio enhances shear performance, showing 17.3% improvement in bearing capacity, 76.1% increase in ductility, and 71% boost in energy dissipation capacity; 3) Steel plate strains at joints remain below 350 microstrain, staying within elastic range to satisfy replaceability requirements. These findings provide valuable references for the design and construction of prefabricated structures.