To provide a telescopic steering device having a structure such that an inner column can be stably held on an inner-diameter side of an outer column.

An outer column 13d and a movable-side bracket 22b are bulgingly molded in one body by a hydroforming method, etc. Further, respective bulge parts 23a, 23a constituting a support part 26 of the outer column 13d are brought into contact with an outer peripheral surface of the inner column 14c at only three places in a circumferential direction. Furthermore, projection parts 31 which protrude from both breadthwise outer side faces of held plate parts 25a, 25a of the movable-side bracket 22b in breadth directions are formed at a periphery of an axially intermediate part of a column-side through hole 30 on the breadthwise outer side faces. Then breadthwise inside surfaces of support plate parts 28, 28 of a fixed-side bracket 12b and breadthwise outer side faces of the projection parts 31 are brought into contact with each other in an assembled state.