To easily fix boots.

For this binding 10, the both side parts of a frame 22 are made to a stepping guide parts 24 bent upwards and locking blocks 28a and 28b are freely turnably attached to the respective stepping guide parts 24. The locking blocks 28a and 28b are turned as shown by arrows 50 and 52 through a fixing metal fitting 40 by the stepping operation of a boot and turned as shown by the arrows 34 and 36 through a locking spring when the fixing metal fitting 40 is arranged on a base 12, a locking part 42 is engaged with the fixing metal fitting 40 and the boot is fixed on the binding 10. The turning center O of the locking blocks 28a and 28b is made eccentric to a tip side oblique upper part to the radius curvature center C of a circular arcuate surface for forming the locking part 42 so that the fixation is surely performed even when snow is stuck to the boot.