Aimed at the overlapping problem of range of dimensionless parameter of each fault of rotating machinery under actual working conditions, a fusion fault diagnosis model for rotating machinery based on dimensionless parameters and evidence reasoning (ER) was proposed. The model was taken advantages of using ER algorithm in solving probability uncertainty, fuzzy uncertainty and non-linear fusion.Input signal was converted to the form of belief distribution by the information transformation technology, and then the analytical ER algorithm was adopted to fuse the input data. Finally, the diagnosis results were achieved through a simple decision rule. Experimental analytic result demonstrates that the method can remarkably improve recognition ratio of fault diagnose for rotating machinery equipment.