To provide a mechanical joint of a steel pipe pile manufacturable at low cost and having high reliability.

This joint comprises an outer joint member 3 and an inner joint member 4. In the inner joint member 4, a thick-wall ring-shaped flange part 13 is formed integrally with the end edge of a thick-wall tubular base 8. The outer diameter of the flange part is generally equal to the outer diameter of a steel pipe pile to be joined thereto. The outer diameter of the base 8 is slightly smaller than the inner diameter of the outer joint member 3. The end surface of one steel pipe pile is aligned with each other and welded to the end surface of the flange part 13. A plurality of pin insertion holes 10 are circumferentially formed in the peripheral wall 16 of the base 8. The outer joint member 3 has an outer diameter generally equal to the outer diameter of the steel pipe pile and an inner diameter slightly larger than the outer diameter of the base 8, and axially aligned with the end surface of the other steel pipe pile and welded thereto. Pin insertion holes 12 of the same diameter are so formed as to correspond to the pin insertion holes 10 drilled in the base 8, and pins 18 are inserted into and connected to the pin insertion holes 10, 12.