A steering apparatus, comprising: a steering shaft having a steering member coupled thereto; a steering column rotatably supporting the steering shaft and being pivotable about a tilt center; a first bracket that includes a first side plate having a tilt elongate hole as a first through hole and that is fixed to a vehicle body; a second bracket that includes a second side plate having a second through hole and that is fixed to the steering column; and a lock mechanism including a fastening shaft that is passed through the tilt elongate hole and the second through hole, an operation lever that rotates together with the fastening shaft, a fastening mechanism that includes a fastening member supported by the fastening shaft and that translates a rotary motion of the operation lever in a lock direction into a linear motion of the fastening member in an axial direction of the fastening shaft to fasten the first side plate to the second side plate by the fastening member, and a gear lock mechanism that performs a gear lock operation when the fastening is carried out by the fastening mechanism; wherein the fastening member includes a main body facing the first side plate, and a guided projection which extends from the main body into the tilt elongate hole, which is guided by the tilt elongate hole when tilt adjustment is made, the gear lock mechanism includes a first tooth row forming member that is provided on the first side plate and that forms a first tooth row formed by parallel teeth arranged in a tilt direction, and a second tooth row forming member that forms a second tooth row formed by parallel teeth that mesh with the first tooth row (f) in a lock operation, and that is interposed between the main body of the fastening member and the first side plate and rotatably supported by the fastening shaft, and the fastening member includes a restricting portion (47a, 48b, 49b, 50b) that restricts rotation of the second tooth row forming member about a central axis of the fastening shaft, to a predetermined range with respect to the fastening member, characterized in that rotation of the guided projection is restricted with predetermined play by the tilt elongate hole, and in the lock operation of rotating the operation lever in the lock direction, the fastening member rotates in the range of the play in the lock direction while pressing the second tooth row forming member toward the first side plate, wherein, with the rotation of the fastening member, the second tooth row forming member also rotates via the restricting portion. a steering shaft having a steering member coupled thereto; a steering column rotatably supporting the steering shaft and being pivotable about a tilt center; a first bracket that includes a first side plate having a tilt elongate hole as a first through hole and that is fixed to a vehicle body; a second bracket that includes a second side plate having a second through hole and that is fixed to the steering column; and a lock mechanism including a fastening shaft that is passed through the tilt elongate hole and the second through hole, an operation lever that rotates together with the fastening shaft, a fastening mechanism that includes a fastening member supported by the fastening shaft and that translates a rotary motion of the operation lever in a lock direction into a linear motion of the fastening member in an axial direction of the fastening shaft to fasten the first side plate to the second side plate by the fastening member, and a gear lock mechanism that performs a gear lock operation when the fastening is carried out by the fastening mechanism; wherein the fastening member includes a main body facing the first side plate, and a guided projection which extends from the main body into the tilt elongate hole, which is guided by the tilt elongate hole when tilt adjustment is made, the gear lock mechanism includes a first tooth row forming member that is provided on the first side plate and that forms a first tooth row formed by parallel teeth arranged in a tilt direction, and a second tooth row forming member that forms a second tooth row formed by parallel teeth that mesh with the first tooth row (f) in a lock operation, and that is interposed between the main body of the fastening member and the first side plate and rotatably supported by the fastening shaft, and the fastening member includes a restricting portion (47a, 48b, 49b, 50b) that restricts rotation of the second tooth row forming member about a central axis of the fastening shaft, to a predetermined range with respect to the fastening member, characterized in that rotation of the guided projection is restricted with predetermined play by the tilt elongate hole, and in the lock operation of rotating the operation lever in the lock direction, the fastening member rotates in the range of the play in the lock direction while pressing the second tooth row forming member toward the first side plate, wherein, with the rotation of the fastening member, the second tooth row forming member also rotates via the restricting portion.