An engine generator device configured so as to require a reduced installation space, reduced facility costs, and reduced running costs and so as to enable the engine to be started by smoothly driving an air motor. An engine generator device (EG) is juxtaposed to firefighting equipment (14) which extinguishes a fire by ejecting nonflammable gas contained within a gas container (11). The engine generator device (EG) is provided with an air motor (10) which starts the engine (1) and also with a start valve unit (12) which is activated by a start command, adjusts the pressure of the nonflammable gas from the gas container (11), and supplies the nonflammable gas to the air motor (10).
