To solve the problem that the play of a movable cam member and an operating lever with respect to a fixed cam member becomes too large in a tilt locking mechanism because the lock of a steering column is released by enlarging the axial displacement by means of a cam.

The steering system is composed of a tilt bolt 8 which is inserted into an elongated hole 6 of a car body side bracket 3 connected to the car body and a hole 7 of a column side bracket 5 connected to a steering column 1 and is restrained so as not to turn, the fixed cam member 9 having a through hole 9b into which the tilt bolt 8 restrained so as not to turn is inserted, the movable cam member 10 which has a through hole 10a, into which the tilt bolt 8 is inserted, and rotatably engages with the fixed cam member 9, the operating lever 11 connected to the movable cam member 10, and a nut 12 which is screwed onto the tilt bolt 8 and positions the operating lever 11 in the axial direction. A sleeve 10b is protrusively formed on the edge of the through hole 10a of the movable cam member 10 and is slidably fitted into the through hole 9b of the fixed cam member 9.