PURPOSE: To prevent a liquid inside a vessel from leakage without fail, by giving a sealing function to a stopper regulating a projecting position of a piston, in case of a manual dispenser which sucks up the liquid into a cylinder with a slide motion of the piston and makes it flow out under pressure.

CONSTITUTION: When a piston 14 being solidly together with a head 16 is made to go up to its projecting position by dint of a compression spring 52, the inside of a pressure chamber is made into suction pressure whereby the liquid inside the vessel is sucked up to the inside ot the pressure chamber 36 by the opening of a primary valve 26 via a suction pipe 30 and a liquid inflow hole 22. Next, when the head 16 is pressed downward, the liquid inside the vessel 36 is pressurized with down motion in the piston 14 whereby a valve body 42 of a secondary valve 38 is separated from the valve seat, thus the luqiud is discharged out of an outflow passage 32. Under the condition aforesaid that the piston 14 is depressed down and locked with engagement between engaging projections 68 and 70, a valve holder 34 at the piston lower end supports the primary valve 26 as closed, while an annular part 60 of a stopper 56 engages an inner circumference of the head 16, so that a liquid leakage in time of the vessel being turned upside down, etc., is obviated with certainty.