Abstract: The present invention provides a method and apparatus for starting an engine which can decrease the amount of compressed air consumed by air motors and can lessen an increase in a size of a compressed air tank and an increase in a size of an air compressor, and in a method of starting an engine using a plurality of air motors, the number of air motors being operative is decreased before the engine can start increasing its engine speed for itself, at starting. That is, during increasing of the engine speed of the engine at the starting, the number of air motors being operative is decreased from, for example, two to one.

Abstract: Disclosed are a method and a device for starting an engine, in which the amount of compressed air consumed by air motors can be reduced and increase in the sizes of a compressed air tank and an air compressor can be suppressed. The method for starting an engine (1) with use of a plurality of air motors (2, 3) is characterized in that the numbers of the air motors (2, 3) to be driven during starting of the engine is reduced before the engine (1) increases the rotational speed by itself: Namely, while the rotational speed of the engine (1) is raised during stoning of the engine, the numbers of the air motors (2, 3) to be driven is reduced, for example, from two to one.