To provide a structure capable of stably holding an inner column 14c on an inner diameter side of an outer column 13d.

An outer column 13d is molded by expanding a hollow tube radially outwards by a hydroform method. Also, a movable side bracket 22b is expanded and molded by the hydroform method integrally with the outer column 13d. Further, respective raised parts 23a, 23a constituting a support part 26 of the outer column 13d and an outer peripheral surface of an inner column 14c are brought into contact only at three parts in a circumferential direction.