Abstract: To address the poor seismic performance and low construction efficiency of prefabricated building structural joints, this study proposes a novel prefabricated concrete column-steel beam joint with steel hoop plate connections. A finite element model of the joint was developed using ABAQUS and validated against full-scale cyclic loading tests. Parametric analysis demonstrated that increasing the steel hoop plate thickness improves joint stiffness and load-bearing capacity, while a higher internal diaphragm thickness (within a practical range) enhances initial stiffness; however, axial compression ratio has minimal influence on these properties. Based on these findings, a preliminary design-stage formula for estimating the joint's shear capacity was derived.