A liquid dispensing valve having a body portion hermetically mounted to a free end of a discharge nozzle of a reservoir and defining a seat; a rod carrying a seal and being selectively displaced between a closing position in which the seal is seated on the seat, and a maximum opening position in which the seal is spaced from the seat; a cap portion hermetically affixed to the body portion downstream the seat and around the rod, and defining a discharge chamber; and an elongated spout having a discharge end turned downwards, said cap portion and elongated spout being configured and dimensioned so that, when the seat is closed, the mass of residual liquid contained in the discharge chamber forms, inside the latter, a vacuum which is sufficient to retain said mass of liquid inside the dispensing valve.