A series of experimental tests with approximately l/2 scaled joint models between a steel pile and a reinforced concrete beam have been carried out to investigate the mechanical behavior，especially the ultimate load bearing capacity and the relationship between bending moment and rotational angle at thejoint. As a result，it was confirmed that tbe joint showed excellent structural performance，that is，its load bearing capacity did not degrade up to the ductility factor of about 5 at least. And it was also indicated that an amount of reinforcing bar affected the stiffness and load bearing capacity of the joint. Furthermore，a numerical approach has been newly developed for the joint based on a two-Stage，two-dimensional analysis to account for the three-dimensional behaviorof the joint. The validity of the new approach was verified by applying to the tested joint models.