The end effector has a first hand and a second hand which can be driven independently from each other. The first hand has a hand body which can be inserted between vertically adjacent substrates stored in a substrate storing portion, holding a substrate immediately above or immediately below the hand body. The second hand has a hand base portion which at least partially advances below a lowermost substrate or above an uppermost substrate of a plurality of substrates stored in a substrate storing portion and a substrate holding means provided to the hand base portion so as to hold two or more substrates including the lowermost substrate or the uppermost substrate. By the end effector, substrates can be conveyed without any problem even when use of a batch conveying type hand is restricted due to the condition on the substrate storing portion side.