Theoperating and power components of the helicopter much, the faults ofthem would lead to hazardous flight accidents easily.On the other hand, with the improvement and complexity of the helicopter, theexpenses of the development, usage andmaintenanceincreased significantly. In order to ensure that the successful task and intactequipment of the helicopter, while reducing maintenance expenses, the health monitoring and fault diagnosis whichof the whole life cycle by helicopter, has become urgent and important.Based on the engineering process of the Testability technology, bythe analysis of the safety requirements and maintenance of the helicopter, this paperexpound the design and verification of the helicopterhealth monitoring and fault diagnosissystem. Corresponding to the each life cycle of the helicopter, the design and verification of this systemincludedthe determination of index, the design and analysis ofdiagnosis, the experiment and verification, the evaluation and improvement of usage.