A steering lock device includes a supporting bracket which is attached to a steering lock body including a lock member restricting rotation of a steering shaft within a steering column and is fastened to the steering lock body to fix the steering lock body to the steering column. The supporting bracket includes a shaft supporting portion pivotally supported by a supporting shaft; a shaft support cancellation preventing portion preventing to cancel the pivotable support of the shaft supporting portion by the supporting shaft; and an engagement holding portion holding the shaft support cancellation preventing portion. The steering body is provided with bearing portions through which the supporting shaft is inserted.