In order to study the lap length of precast concrete U-shaped steel ring buckle connection, one cast-in-place beam column joint specimen and three contrast specimens with different lap length of U-shaped steel ring buckle connection were made. The low cycle repeated quasi-static test was carried out to observe the failure mode of each specimen, study its hysteretic behavior, bearing capacity, deformation capacity and stress development process of reinforcement, and analyze the U-shaped steel ring buckle connection of precast concrete The reasonable lap length of T-bar ring buckle connection. The results show that the bearing capacity of fabricated joints is higher than that of cast-in-place joints. The ductility and energy dissipation capacity of specimens with different lap lengths are different. The increase of lap length is conducive to the improvement of seismic performance such as bearing capacity, ductility and energy dissipation capacity. On the basis of experiments, this paper regresses the reasonable lap length of U-shaped steel ring buckle connection. Some suggestions are put forward for the optimal design of the prefabricated concrete U-shaped reinforced ring buckle joint, which can provide reference for the engineering application and further theoretical research of the joint.