A scroll fluid machine comprises a stationary scroll and an orbiting scroll fitted on an eccentric portion of a driving shaft. The stationary scroll has a stationary end plate from which inner and outer stationary wraps project, and the orbiting scroll has an orbiting end plate from which inner and outer orbiting wraps project. Between the stationary and orbiting end plates, inner and outer annular partition walls are provided. Inside the inner partition wall, the inner stationary wrap is engaged with the inner orbiting wrap to form an expanding region, and between the inner and outer partition walls, the outer stationary wrap is engaged with the outer orbiting wrap to form a compressing region. A bore is formed through the orbiting end plate so that fluid expanded and cooled in the expanding region flows from the expanding region to rear surface of the orbiting end plate to cool the orbiting end plate.