A vapor phase growth apparatus of an embodiment includes: a reaction chamber; a gas supply path connected to an organic metal supply source at a first connection, the gas supply path being connected to a carrier gas supply source, the gas supply path supplies a process gas including organic metal and a carrier gas into the reaction chamber; a gas discharge path connected to the organic metal supply source at a second connection, the gas discharge path discharges the process gas to the outside of the apparatus; a first mass flow controller and a first adjustment device provided at the gas supply path; a second adjustment device provided at the gas discharge path; and a shortcut path connecting the gas supply path to the gas discharge path. One of the first and the second adjustment device is a back pressure regulator, and the other is a mass flow controller.