Rotation bending fatigue tests at room and liquid nitrogen temperatures were carried out on 2024-T4, 5056-H32 and 1050-H18 alloys. The fatigue strength is much greater at the liquid nitrogen temperature than at room temperature. Both the ratio of the fatigue strength at the liquid nitrogen temperature to that at room temperature and the ratio of fatigue strength to ultimate strength of 5056-H32 alloy are greater than those of 2024-T4 alloy. The fatigue strength of 5056-H32 alloy at the liquid nitrogen temperature is nearly equal to that of 2024-T4 alloy. Therefore, when the fatigue strength at cryogenic temperature is significant, 5056-H32 having excellent weldability would be more favorable than 2024-T4 alloy.