A liquid tank (14) for an aerosol inhalator has a reservoir channel (68) opening into air at one end thereof and containing flavor solution (L) inside a supply pipe (48) connecting the other end of the reservoir channel (68) to an inhalation passage (4) of the aerosol inhalator and guiding the flavor solution (L) to the inhalation passage (4) through either one of inhalation pressure in the inhalation passage (4) and capillary action and an outflow valve (26) located between the other end of the reservoir channel (68) and the supply pipe (48), for allowing only the flow of the flavor solution (L) running from the reservoir channel (68) towards the supply pipe (4) (FIG.2).