A construction machine includes a vertical separating/connecting device interposed between a lower traveling body and a swing bearing that supports an upper rotating body. The device includes an externally toothed ring member fixed to the swing bearing with a first attaching unit, a rotating unit that rotates the externally toothed ring member, an internally toothed ring member fixed to the lower traveling body with a second attaching unit positioned on an attachment pitch circle having the same diameter and center as an attachment pitch circle of the first attaching unit, and a fixing unit that fixes the externally toothed ring member or the internally toothed ring member. Internal teeth of the internally toothed ring member and external teeth of the externally toothed ring member are positioned so as to allow the movement of the external teeth or to engage with each other when the externally toothed ring member is rotated.