The invention relates to a device and method for controlling the operation of a thermal spray torch (12). The inventive device and method are characterised in that an on-board camera (54) and pyrometer (70) are used to measure the properties of the jet (16) and the temperature of the deposit (24) on the part (22) and in that the correction to be made to the supply parameters of the torch (12) is deduced. Furthermore, the invention is characterised in that the corrected parameters are sent to the cabinet (30) that controls the torch (12).