This study analyzes stress, fatigue and vibration on main rotor and body of helicopter. The maximum stress is shown on adjoint part between body and main rotor at the lower position of main rotor. As the maximum displacement amplitude is happened at 4000Hz, there is no resonance and the state of helicopter becomes safe at hovering without the abnormal air current and the disabled rotor. Among the cases of nonuniform fatigue loads, "SAE bracket history" with the severest change of load becomes most unstable but "Sample history" becomes most stable. In case of "Sample History" with the average stress of 0MPa to -105MPa and the amplitude stress of 0MPa to 8.539×105MPa, the possibility of maximum damage becomes 3%. This stress state can be shown with 5 times more than the damage possibility of "SAE bracket history" or "SAE transmission". The structural result of this study by using the analysis of vibration and fatigue can be effectively utilized for safe and durable design of helicopter.