A substrate processing apparatus includes a plurality of evacuable treatment chambers connected to one another via an evacuable common chamber, and the common chamber is provided with means for transporting a substrate between each treatment chamber. More specifically, a substrate processing apparatus includes a plurality of evacuable treatment chambers, at least one of said treatment chambers having a film formation function through a vapor phase reaction therein, at least one of said treatment chambers having an annealing function with light irradiation and at least one of said treatment chambers having a heating function therein. The apparatus also has a common chamber through which said plurality of evacuable treatment chambers are connected to one another, and a transportation means provided in said common chamber for transporting a substrate between each treatment chamber.