To achieve a structure capable of stably holding an inner column, on the inner diameter side of an outer column.

The outer column 13d is formed by swelling a hollow pipe outside in the radial direction by a hydroforming process. A movable side bracket 22b is also formed by swelling by the hydroforming process integrally with the outer column 13d. Respective protrusion parts 23a and 23a for constituting a support part 26 of the outer column 13d and an outer peripheral surface of the inner column 14c are allowed to abut only in three places in the circumferential direction.