Abstract: An adjustable gastric banding device is used for contracting a patient's stomach in order to fight obesity. A gastric band (1) of a known type, implanted around the stomach and including a cavity (2) filled with liquid, is connected by a tube (7) to a control box (9) and a balancing reservoir (11) which are implanted under the patient's skin. The box (9) contains an electric pump and an electronic control unit capable of communicating by radio with a monitor (13) carried by the patient and with a controller (12) intended for the doctor. The controller can operate the pump by remote control to transfer determined volumes of liquid in a closed circuit from the gastric band to the reservoir or vice versa, to adjust the diameter of a passage in the stomach. The monitor receives and signals alarms from the control box.