According to the rub-impact fault of rotating machinery, the diagnosis method based on variational ｍode decomposition (VMD) and Hilbert spectrum is studied. The fault signal is decomposed into a series of ｉntrinsic ｍode ｆunction (IMFs) by VMD method. The result of VMD is compared with that of EEMD. The time-frequency characteristic of the fault signal is analyzed by the Hilbert spectrum. The result shows that the proposed diagnosis method can accurately show the frequency components of the fault signal. Compared with the traditional method based on frequency spectrum analysis,the proposed method can show the relationship between frequency and time. Compared with the method based on EEMD, this proposed method can effectively inhibit mode mixing and accurately show the fault information. The experimental result shows that the presented diagnosis method is feasible and valid.