Enhanced oil recovery method consisting in continuously dissolving, in the injection water, a stable invert emulsion of acrylamide (co)polymer containing at least one inverting agent, and a water soluble polymer, whereby: in a first step, the emulsion is prediluted in a first static mixer to a (co)polymer concentration of at least 5 g/l, the difference of pressure between the mixer outlet and inlet being at least 2 bar, in a second step, the suspension from the first mixer is diluted in a second static mixer to a concentration corresponding to the injection concentration of the water in the well of between 500 and 3000 ppm, the difference of pressure between the mixer outlet and inlet being at least 1 bar.