A fluid dispenser comprising: a fluid reservoir (10) serving to contain fluid; and a dispenser head (2) mounted on the reservoir (10) to take fluid from the reservoir, said head (2) defining a dispensing chamber (26) communicating with the reservoir via an inlet valve (25, 215) and communicating with the outside at a dispensing orifice via an outlet valve (237, 222); said dispenser being characterized in that the chamber (26) comprises at least one elastically deformable actuating wall (231) that is depressed in order to generate a pressure inside the chamber that is high enough to close the inlet valve and to open the outlet valve.