A sport boot that can be converted to adapt to a variety of sports, especially gliding sports. The sole of the boot is constituted of an irremovable base affixed to the shell, and on which front and rear vertical retention zones are obtained, on the one hand, and of front and rear sole portions that are distinct, interchangeable and complementary to the sole base to which they adapt to constitute the tip and the heel, respectively, and being selected by the user among at least two sets of front and rear sole portions whose profiles and dimensional characteristics are capable of allowing, relative to the front and rear zones for the axial retention of the fixed base and complementarily with the latter, to recontitute and adapt a sole from the same boot, conforming to one binding standard or another.