A steering column device, comprising: a steering column for supporting a steering shaft in a freely rotatable manner; a guide plate having a guide groove extending in a fore-and-aft direction of a vehicle along a column axis direction, the guide plate being fixed to a vehicle body at a position above the steering column; a column bracket for supporting the steering column at a position below the guide plate, the column bracket being assembled onto the guide plate so as to be movable toward a front of the vehicle relative to the guide plate; a coupling member coupled to the column bracket through the guide groove of the guide plate, the coupling member being movable along the guide groove when the column bracket moves toward the front of the vehicle relative to the guide plate; and an upper column cover assembled above the steering column at a position corresponding to a vehicle rear of the guide plate, characterized in that the upper column cover is movable toward the front of the vehicle together with the steering column, the guide plate comprises, at a vehicle rear portion thereof, means for mitigating an impact to be caused when the upper column cover strikes, in an event of collision of the vehicle, against the vehicle rear portion of the guide plate along with movement of the steering column toward the front of the vehicle together with the column bracket; the means for mitigating an impact comprises means for guiding the upper column cover toward a lower side of the guide plate, the means for guiding comprises a breaking portion (33a, 33b) for breaking an upper front portion of the upper column cover. a steering column for supporting a steering shaft in a freely rotatable manner; a guide plate having a guide groove extending in a fore-and-aft direction of a vehicle along a column axis direction, the guide plate being fixed to a vehicle body at a position above the steering column; the guide plate being fixed to a vehicle body at a position above the steering column; a column bracket for supporting the steering column at a position below the guide plate, the column bracket being assembled onto the guide plate so as to be movable toward a front of the vehicle relative to the guide plate; the column bracket being assembled onto the guide plate so as to be movable toward a front of the vehicle relative to the guide plate; a coupling member coupled to the column bracket through the guide groove of the guide plate, the coupling member being movable along the guide groove when the column bracket moves toward the front of the vehicle relative to the guide plate; and the coupling member being movable along the guide groove when the column bracket moves toward the front of the vehicle relative to the guide plate; and an upper column cover assembled above the steering column at a position corresponding to a vehicle rear of the guide plate, characterized in that the upper column cover is movable toward the front of the vehicle together with the steering column, the upper column cover is movable toward the front of the vehicle together with the steering column, the guide plate comprises, at a vehicle rear portion thereof, means for mitigating an impact to be caused when the upper column cover strikes, in an event of collision of the vehicle, against the vehicle rear portion of the guide plate along with movement of the steering column toward the front of the vehicle together with the column bracket; the means for mitigating an impact comprises means for guiding the upper column cover toward a lower side of the guide plate, the means for guiding comprises a breaking portion (33a, 33b) for breaking an upper front portion of the upper column cover.