In a scroll compressor according to the present invention, at least one injection port penetrating a second end plate of a fixed scroll at a position where the injection port is open to a first compression chamber or a second compression chamber in a compression stroke after the suction refrigerant is introduced and closed. Further, the discharge bypass port is disposed such that a volume ratio, which is a ratio of a suction volume to a discharge volume of the second compression chamber at which the refrigerant in the first compression chamber can be discharged, is smaller in the first compression chamber, which is one compression chamber having the large amount of the refrigerant injected from the injection port, than in the second compression chamber, which is the other compression chamber among the first compression chamber and the second compression chamber.