To provide a tying system 1 which can easily tie steel bars 3 thickly.

This tying system 1 is equipped with a base frame 5, a left arm 7, a right arm 9, a first stretching/contracting section 11, a second stretching/contacting section 13, a pressing section 15, a wire 17, a carrying roller 19, a pair of right and left guide rollers 21, a band-feeding section 23, and a wire-tying head 25. A large number of steel bars 3 are mounted on the carrying roller 19. When the first stretching/contracting section 11 stretches, the right arm 9 turns in such a manner that the distal end of the first stretching/ contracting section 11 may move to the left direction, and the left arm 7 turns in such a manner that the distal end may move to the right direction. Thus, the large number of steel bars 3 are wrapped with the wire 17 and clamped. At the almost same time, the second stretching/contracting section 13 stretches, and a contact plate 43 presses the steel bars 3. By the pressing, the alignment of the steel bars 3 is collapsed, and the competition between the steel bars 3 with each other is suppressed. The steel bars 3 are densely tied with a band which is fed from the band-feeding section 25.