It’s very important to describe the corrosion damage evolvement rule of the aircraft structure for evaluating the calendar life. According to equivalent accelerated corrosion testing spectrum based on key environment data, the corrosion damage of accelerating corrosion testing for 7d is equivalent to that of field exposure for 1a. The new aluminum alloy of aircraft structure has been accelerated tested for 10a. Through KH-7700 3-D optical microscope, corrosion damage was inspected and measured. The result shows that some independent pits generate on the alclad surface in the first, and then many pits interconnect leading to the bigger holes. The effective service life of the aluminum alclad was gotten under equivalent accelerated corrosion testing condition.