Provided is a vaporizer capable of reducing the occurrence of bumping in a vaporization space and thereby minimizing the pressure fluctuations therein, when a method not using an atomizer is employed. A vaporizer (1) includes a tank body (10), a porous member (30) disposed in the vaporizer (1) and heated, a supply tube (40) configured to supply a liquid material (L) to the porous member (30), and a gas discharge passage (7) configured to discharge a source gas (G) produced by vaporizing the liquid material (L) to the outside. An outlet (41) of the supply tube (40) is disposed in contact with or in close proximity to the porous member (30). When the outlet (41) is disposed in close proximity to the porous member (30), a separation distance (H) between the outlet (41) and the porous member (30) is not greater than a distance from the outlet (41) to a bottom of a droplet of the liquid material (L) formed and suspended at the outlet (41) by surface tension.