Abstract: A mounting mechanism for mounting a compressor in an engine compartment of a car comprises at least two plate members fixed to and projecting outwardly of the compressor at circumferentially spaced locations thereof, and at least two mount stay members fixed in the engine compartment and extending towards the compressor so as to lie in superposed face-to-face relationship with respective ones of the plate members. A bolt extends through one pair of superposed plate and mount members so as to pivotally mount the compressor for pivotal turning movement about the bolt to thereby enable adjustment of the position of the compressor. An elongate slot is formed in either the plate member or mount member of another pair of superposed plate and mount and the inner surface of the slot is provided with a toothed surface.