The invention relates to a vertebral fixation system comprising two fixation parts (1) which each have a pedicular element (2) that can be engaged in a vertebral pedicle and are connected to each other by a connecting element. The connecting element is a flexible strip (6), the pedicular elements are screws, and each fixation part comprises a fixation head (3) on a rod (4) secured to means (5) for adjustably locking the flexible strip under tension in relation to the head.