In the fuel cell vehicles, there is usually a falling-off in durability caused by the inflow of air into a cathode area when the stack is down. In this study, the air cutoff valve was developed which could block the air passage to ensure the durability of the stack. Unlike a typical valve, it is important to secure the stability for preventing malfunction in the operation. And it must operate normally when the exhaust gas containing much moisture is frozen around the valve by the low temperature in winter. A valve satisfying conditions above was designed in this study. Then, some tests were carried out on a test rig and a vehicle to verify the improvement of durability of a fuel cell stack.