The present invention relates to a substrate conveyance apparatus (200). The apparatus includes a main frame (230), a substrate support device (240) and a base plate (210). The substrate support device includes robot blades (141a, 141b) and a holding chuck (145). The holding chuck is movably connected with main frame so as to hold the robot blades. The robot blades are comprised of two pair of plate-shaped members, and the base plate is used to support the main frame. The distance between one pair of plate-shaped members is different from that of the other pair of plate-shaped members. The substrate conveyance apparatus is used to load/unload the substrates with different sizes.