A bone anchoring device for a spinal column fixation system includes an anchoring part, a bearing part for mounting at least one connection element thereon and a fixing element. The connection element is adapted for fixing to at least two bone anchoring devices. The anchoring part and the bearing part are mounted on each other, movable relative to each other in an assembly position and fixable relative to each other by the fixing element in an implantation position. The fixing element is of integral construction and has a proximal fixing element section, a distal fixing element section and a predetermined break-off area formed between the proximal and distal fixing element sections. The distal fixing element section has a receptacle for engagement with a tool for transferring the bone anchoring device from the assembly position to the implantation position. The device may be part of an improved spinal column fixation system.