Abstract: The invention relates to a mechanical control device for a disc brake. The mechanical control device comprises two members 28, 32, 128, 132 extensible in an axial direction with respect to the brake disc upon relative rotation therebetween. These members are respectively connected to a control member 34, 134 and to a piston 20, 120 associated with a friction member 22, 122. Adjusting means 56, 156 comprise an annular element 58, 158 cooperating by way of one-way toothings 60, 62 with the member 28, 128 connected to the control member in order to turn relative to member 28, 128 upon brake actuation, when the wear of the friction member 22, 122 is greater than a predetermined value. Upon return of the control member 34, 134 to its idle position, a friction spring 48, 148 inserted between the piston 20, 120 and the member 28, 128 permits this member 28, 128 to turn relative to member 32, 132, thus adjusting for the wear of friction member 22, 122.