A spray device includes a nozzle that forms a channel for supplying liquid to at least one opening for spraying the liquid outside the device, and, close to the opening, a first and a second electrode arranged in such a way as to inject electric charges into the liquid. The edge of the opening includes, on one side of the channel, at least one projecting end of the first electrode that projects into the channel and is to be brought into contact with the liquid, and on the other side of the channel, an electrically insulating nozzle body in which the second electrode is embedded adjacently to the first electrode, in such a way that the intensity of the electrostatic field in the or each projecting end is maximized.