An adjustment device for adjusting a vehicle seat component is provided. The adjustment device comprising a rotary fitting for adjusting the vehicle seat component, which includes a first fitting part and a second fitting part pivotally mounted with respect to the first fitting part about an axis of rotation, a drive device connected with the rotary fitting for driving the rotary fitting, and an adjustment element of the drive device for actuating the drive device. The drive device is formed to transmit a force present on the adjustment element on the drive side for adjusting the vehicle seat component to the rotary fitting, but to block a force present on the rotary fitting on the output side. For blocking the output-side force the drive device includes a brake section fixedly arranged on the first fitting part and at least one brake segment which in the presence of an output-side force at the rotary fitting cooperates with the brake section in a braking manner via a contact surface in the manner of a shoe brake.