Abstract: To reveal the mechanism of impact resistance of an inner ring-stiffened tubular K-joint under impact loading, impact tests were carried on four inner ring-stiffened tubular K-joint specimens and one ordinary joint specimen by high performance drop-weight impact machine. The failure mode of the joint was obtained and time history curves were analyzed. The finite element numerical analysis model of inner ring-stiffened tubular K-joint was established and the reliability of the model is verified by comparison with the test data, and the influence of the stiffening ring geometric parameters on the impact resistance index of the joint and the impact energy dissipation mechanism are analyzed. Study results show that inner stiffening ring can improve the stiffness and strength of the joint, both the increase of stiffening ring width and of thickness can improve impact resistance of tubular K-joint, and the improvement of impact resistance of the joint caused by the increase of stiffening ring thickness is