To support the rapid and high-efficient elimination of the vibration fault of complex systems， this paper presents a quanti? tative method of vibration failure mode， which can realize the key verification of the vibration failure mode based on quantifiable value. The technical characteristics of the vibration fault tree analysis is discussed， which points out that fault tree analysis is not suitable for the vibration fault of complex systems. The quantification method of vibration failure mode is proposed， and dimen? sions of fault mode， like the probability of failure mode and the verifiability， are used to quantify. The vibration fault of the core ma? chine of an aviation engine is introduced， and the specific application of the method of vibration failure mode is given. It proves that the quantization method of vibration fault mode has the availability， high efficiency， and the important value of the engineering ap? plication.