Steering locking device

A steering locking device (9) has an annular clearance (33) provided between a steering shaft (3) and a collar (10) surrounding the steering shaft (3). A spacer (11) is press-fitted in the annular clearance (33), to form a circular arc shape surrounding the steering shaft (3). The spacer (11) is wound around the steering shaft (3) from the outside of the collar (10) through the opening (34) of the collar (10). When a locking member (13) supported on a locking device main body (12) is at a locked position, the collar (10) is prevented from being rotated. When a torque applied to the steering shaft (3) is not more than a predetermined torque, the spacer (11) prevents the relative rotation between the steering shaft (3) and the collar (10).