The non-containment problem caused by failure blade affects the safety of aeroengine directly. Traditional containment test is generally conducted un-der the ideal vacuum condition. For more effectively exploring the vibration response of cut-off notch blade in actual operation, this research develops an effective numerical simulation of the pre-notched fan blade by considering the fluid–structure interaction. The results show that the increasing of operating speed makes the maximum stress of notched blade increase rapidly, and the larger notch cross-section raises the natural frequency of notched blade significantly. Aerodynamic bending moment leads to a multiaxial stress on the notched blade, which the contribution is approximately 20% of the total notch stress. Blade-off test is conducted successfully, and the rotational speed of blade-off is nearly 1800 r/min which is consistent with the simulated prediction result. This research provides a certain theoretical basis and reference for the blade cut-off notch design in the non-vacuum containment test.