In order to ensure the long⁃term safe, stable and efficient operation of the rotating machinery, a risk cloud model evaluation method for the rotating machinery rotor system is proposed for the actual risk status of the rotor system. The evaluation method firstly uses FMECA to summarize the failure mode of the rotating machinery rotor system, finds the defects and weak links of its reliability, and identifies the main failure modes that cause the rotor system to fail. Then, based on the stress⁃strength interference model, the three digital characteristics of the rotor system cloud model in the single failure mode are constructed, which combines with the fuzzy and randomness of the cloud model to obtain the risk cloud model evaluation of the rotor system. Qualitative and quantitative results.It is applied to the turbine rotor system, and the rotor system is comprehensively evaluated by MATLAB simulation and visually presented in the form of cloud droplets.