A vertical type semiconductor device producing apparatus comprises a vertical type reaction chamber which is to accommodate a plurality of stacked substrates; an exhaust path which exhausts the reaction chamber, a vacuum exhaust device which exhausts the reaction chamber through the exhaust path; an exhaust valve which opens and closes the exhaust path; a first supply path which supplies a first kind of gas, which contributes to film formation, to the reaction chamber; a second supply path which supplies a second kind of gas, which contributes to the film formation, to the reaction chamber; a first and a second gas supply valves which respectively open and close the first and second supply paths; and a controller which controls the exhaust valve and the first and second gas supply valves such that when the first kind of gas is supplied to the reaction chamber, the first kind of gas is supplied to the reaction chamber from the first supply path in a state in which exhaust of the reaction chamber is being stopped to expose the plurality of substrates in the reaction chamber to the first kind of gas, and when the second kind of gas is supplied to the reaction chamber, the second kind of gas is supplied to the reaction chamber through the second supply path in a state in which the reaction chamber is being exhausted by the vacuum exhaust device to expose the plurality of substrates in the reaction chamber to the second kind of gas.