Device for dosing one or more skin treatment substances, comprising a formula for the treatment of rags and small lesions, as well as for the cure and treatment of other skin diseases, including said formula eugenol and panthenol, comprising also said device a tank (2) for the treatment substances, a dosing element (3) suitable for dosing the substances on the skin, a valve (4) adapted to adequately connect said tank (2) to said element (3 ) dispenser and wherein said valve (4) comprises: - a dosing chamber (5) having a predetermined volume suitable to contain a portion of the treatment substances, - substance passage means (6) adapted to put, of alternatively, said dosing chamber (5) in fluid communication with said tank (2) to fill it or with said dosing element (3) to dose the substances s treatment. and wherein said passage means (6) comprise: - a filling path (7) suitable for filling said dosing chamber (5) and first closing means (9) adapted to selectively obstruct said filling path (7) while that the treatment substances are being dosed； - an outlet path (8) adapted to empty said dosing chamber (5) while the substances are being dosed and second closing means (10) adapted to selectively obstruct said outlet path (8) while said chamber (5) dosing is being filled； - a cannula (11) slidably limited along a longitudinal axis (L) between an extended position to fill said dosing chamber (5) and a retracted position to dose said treatment substances, and wherein the sliding movement said cannula (11) takes place by contacting and pressing the end of said cannula (11) on the surface to be treated； and wherein said valve (4) also comprises a longitudinal hole (14) defining a sliding wall (15) suitable for slidingly accommodating said cannula (11), said second closing means (10) comprising at least one channel ( 16) transverse created in said cannula (11) and having a suitable longitudinal position to allow it to be selectively obstructed by said sliding wall (15) when
