A steering system includes a fastening mechanism that makes an upper jacket fastened to be held by a lower jacket. In a fastened state of the fastening mechanism, a first tooth member on the upper jacket side is meshed with a second tooth member on the lower jacket side. The second tooth member is connected to the lower jacket via a guide shaft (connecting member) that is fracturable during a secondary collision. During the secondary collision in an unfastened state of the fastening mechanism, a second engagement portion (driving member) that moves in a column axial direction integrally with the upper jacket abuts on the second tooth member in an unmeshed state to fracture the guide shaft, and deforms an impact absorbing member via the second tooth member to absorb an impact.