Provided in the present invention are a muffler (2) for use in a refrigerating device and a refrigerating device. The muffler comprises an outer casing (23), an inner wall (24), and a sound absorbing material (26) provided between the inner wall and the outer casing, the inner wall defining a fluid inlet (21), a fluid outlet (22), and a fluid passage deflected between the fluid inlet and the fluid outlet, wherein at least a partial region of the inner wall is provided with perforations (241, 242, 243, 244), and the inner wall has a higher perforation rate at the inner side of the fluid passage than that at the outer side of the fluid passage. The muffler according to the embodiment of the present invention significantly reduces the sound and vibration of the refrigerating device.