An inner ring 4 of a pipe joint 1 includes a bulge portion 6 formed at an axially outer end portion thereof so as to project toward a radially outer side, and to be press-fitted into an end portion of a tube 8, and has a fluid flow passage 4a formed on a radially inner side of the bulge portion 6. The bulge portion 6 is formed so as to be tapered from an axially inner side toward an axially outer end thereof in an axial cross-sectional view, and has a flat surface 6e formed at the axially outer end thereof and extending in a radial direction.