An alpine ski boot (1) including a lower shell part (2) surmounted by an upper (4) which is at least partially articulated (5) on the shell part, and at least one device (6) for controlling the active flexion (flex) of the said upper in the rear/front direction, consisting of a slide whose position can be adjusted transversely in order to define a movable rigid bearing point, at least partially between the lower front border (8) of the articulated upper (4) and a fixed part (9) of the lower shell part (2). It is characterised in that the bearing slide (7) of the flexion-control device (6) of the upper (4) consists of a sliding member capable of being displaced in translation on a guide rail (10) integral with the lower shell part and extending substantially parallel to a part at least of the said lower front border (8) of the upper (4). 展开▼
