A steering column apparatus comprising: a column shaft to which a steering wheel is fixed at a rear end in a front-rear direction of a vehicle; a column tube that supports the column shaft such that the column shaft is rotatable; and an upper bracket that supports a rear part of the column tube, wherein the column tube includes: a lower tube; and an upper tube fitted to the lower tube from a rear side, the upper bracket includes: a vehicle body-side bracket fixed to a vehicle body and including a pair of side plates provided at a distance between the side plates in a width direction of the vehicle; a tube-side bracket fixed to the upper tube and including a pair of side plates provided at a distance between the side plates in the width direction of the vehicle; and a support shaft arranged below the upper tube, the vehicle body-side bracket has first coupling holes in the respective side plates, the tube-side bracket has second coupling holes in the respective side plates, the first coupling holes and the second coupling holes are configured such that the vehicle body-side bracket and the tube-side bracket are coupled together by inserting the support shaft through the first coupling holes and the second coupling holes, and each of the second coupling holes is open rearward and is configured such that, when an axial load equal to or greater than a predetermined load is applied to the upper tube, fitting between the second coupling hole and the support shaft is terminated and the tube-side bracket moves forward, characterized in that the steering column apparatus is mounted on the vehicle in an inclined state such that a front end of the column tube is located below a rear end of the column tube; the vehicle body-side bracket includes: a top plate extending in the front-rear direction of the vehicle and in the width direction of the vehicle; and a rear wall bent so as to extend downward from a rear end of the top plate; and a facing portion (91; 101) bent so as to extend in an axial direction of the upper tube is provided at a part of the rear wall that faces the upper tube, wherein the vehicle body-side bracket has a cutout portion at a part of the rear wall that is adjacent to the facing portion (91; 101) in the width direction of the vehicle. a column shaft to which a steering wheel is fixed at a rear end in a front-rear direction of a vehicle; a column tube that supports the column shaft such that the column shaft is rotatable; and an upper bracket that supports a rear part of the column tube, wherein the column tube includes: a lower tube; and an upper tube fitted to the lower tube from a rear side, a lower tube; and an upper tube fitted to the lower tube from a rear side, the upper bracket includes: a vehicle body-side bracket fixed to a vehicle body and including a pair of side plates provided at a distance between the side plates in a width direction of the vehicle; a tube-side bracket fixed to the upper tube and including a pair of side plates provided at a distance between the side plates in the width direction of the vehicle; and a support shaft arranged below the upper tube, a vehicle body-side bracket fixed to a vehicle body and including a pair of side plates provided at a distance between the side plates in a width direction of the vehicle; a tube-side bracket fixed to the upper tube and including a pair of side plates provided at a distance between the side plates in the width direction of the vehicle; and a support shaft arranged below the upper tube, the vehicle body-side bracket has first coupling holes in the respective side plates, the tube-side bracket has second coupling holes in the respective side plates, the first coupling holes and the second coupling holes are configured such that the vehicle body-side bracket and the tube-side bracket are coupled together by inserting the support shaft through the first coupling holes and the second coupling holes, and each of the second coupling holes is open rearward and is configured such that, when an axial load equal to or greater than a predetermined load is applied to the upper tube, fitting between the second coupling hole and the support shaft is terminated and the tube-side bracket moves forward, characterized in that the steering column apparatus is mounted on the vehicle in an inclined state such that a front end of the column tube is located below a rear end of the column tube; the vehicle body-side bracket includes: a top plate extending in the front-rear direction of the vehicle and in the width direction of the vehicle; and a rear wall bent so as to extend downward from a rear end of the top plate; and a top plate extending in the front-rear direction of the vehicle and in the width direction of the vehicle; and a rear wall bent so as to extend downward from a rear end of the top plate; and a facing portion (91; 101) bent so as to extend in an axial direction of the upper tube is provided at a part of the rear wall that faces the upper tube, wherein the vehicle body-side bracket has a cutout portion at a part of the rear wall that is adjacent to the facing portion (91; 101) in the width direction of the vehicle.