A steering column device comprising: a fixed bracket which includes a first plate fixed to a vehicle body-side member, wherein a first hole being an elongated hole extending parallel to a column movement direction at the time of a secondary collision is formed in the first plate; a movable jacket which rotatably supports a steering shaft having a steering member connected to one end of the steering shaft; a movable bracket which supports the movable jacket so as to move in the column movement direction along with the movable jacket at the time of the secondary collision and includes a second plate facing the first plate, wherein a second hole facing the first hole is formed in the second plate; and a suspension mechanism which is supported on the first plate, suspends the movable jacket through the movable bracket; wherein the suspension mechanism includes a suspension bolt which is inserted into the first hole and the second hole, and a nut which is screwed onto the suspension bolt and connects the first plate and the second plate in cooperation with the suspension bolt, and wherein the suspension bolt includes a head portion; characterised by: the suspension mechanism being configured to move in the column movement direction at the time of the secondary collision, the bolt including a large-diameter portion which is continuous to the head portion with a smaller diameter than the head portion and is inserted into the first hole, a small-diameter portion which is continuous to the large-diameter portion with a smaller diameter than the large-diameter portion and is inserted into the second hole, a stepped portion which is formed between the large-diameter portion and the small-diameter portion and comes into contact with the second plate, and a threaded portion which is provided in the small-diameter portion and is screwed into the nut, the second plate being pinched between the nut and the stepped portion, and the suspension mechanism including a leaf spring which is interposed between the head portion and the first plate, thereby biasing the first plate to the second plate side. a fixed bracket which includes a first plate fixed to a vehicle body-side member, wherein a first hole being an elongated hole extending parallel to a column movement direction at the time of a secondary collision is formed in the first plate; a movable jacket which rotatably supports a steering shaft having a steering member connected to one end of the steering shaft; a movable bracket which supports the movable jacket so as to move in the column movement direction along with the movable jacket at the time of the secondary collision and includes a second plate facing the first plate, wherein a second hole facing the first hole is formed in the second plate; and a suspension mechanism which is supported on the first plate, suspends the movable jacket through the movable bracket; the suspension mechanism being configured to move in the column movement direction at the time of the secondary collision, the bolt including a large-diameter portion which is continuous to the head portion with a smaller diameter than the head portion and is inserted into the first hole, a small-diameter portion which is continuous to the large-diameter portion with a smaller diameter than the large-diameter portion and is inserted into the second hole, a stepped portion which is formed between the large-diameter portion and the small-diameter portion and comes into contact with the second plate, and a threaded portion which is provided in the small-diameter portion and is screwed into the nut, the second plate being pinched between the nut and the stepped portion, and the suspension mechanism including a leaf spring which is interposed between the head portion and the first plate, thereby biasing the first plate to the second plate side.