A supporting unit of a telescopic adjustment mechanism is placed within an opening hole formed at one end side of an outer jacket and fixed to an outer peripheral surface of an inner jacket. A tip of a screw axle which is movable in an axial direction of a jacket is linked to the supporting unit. The inner jacket placed at an inside of an outer jacket is pressed on an inner peripheral surface of outer jacket by means of a biasing mechanism placed at an opposite side of the opening hole. Thus, positions of the supporting unit and the biasing mechanism along the axial direction of the jacket are substantially coincident with each other and the supporting unit is placed within the outer jacket in the axial direction of the jacket. Consequently, a steering column apparatus can be small-sized in the axial direction of the jacket.