The invention provides a method for evaluating vacuum plume effect on basis of mutual coupling of experiment and simulation and aims to quickly and accurately evaluating the vacuum plume effect in rocket engines. The method includes: performing simulation aided experimental design, to be specific, performing initial simulation to determine typical experimental conditions and key measurement parameters; confirming experimental effectiveness, to be specific, comparing experimental data of an experimental process with initial simulation results, and judging the effectiveness; confirming method effectiveness, to be specific, after confirming experimental effectiveness, subjecting a simulation method to verification and correction to allow sufficient precision; computing popularization of the simulation method, to be specific, subjecting all conditions of a plume effect task to be analyzed to simulation computation by the simulation method verified. The method has the advantages that various specific analytical problems about the engine vacuum plume effect can be studied and evaluated quickly, efficiently and accurately, reasonableness of experimental design can be effectively guaranteed, fewer experiment times are required, and experiment cost is lowered.