Abstract: A method and device are disclosed for calibrating a regulated flow spraying apparatus of the type including a source of spraying fluid under pressure, and spray nozzles, the flow rate of the spray nozzles being regulated by varying the pressure of the liquid delivered thereto, the regulation being controlled as a function of at least one external parameter and a calibration parameter. Fluid from the source is conveyed to a calibration circuit comprising a flow rate sensor and at least one calibration nozzle. The flow rate and the pressure of the fluid are measured in the claibration circuit. The calibration parameter is calculated from the measured values of the flow rate and pressure.