Considering the complexity of surrounding rock classification,some factors such as rock uniaxial compressive strengthen,integrality coefficient of rock mass,the angle between tunnel axis and the main joint,joints condition and seepage measurement of groundwater are selected as evaluation indexes.The evaluation indexes and the standard for surrounding rock classification are used to constitute a set pair.A model of tunnel surrounding rock classification based on set pair analysis is established,which is tested by measured samples of surrounding rock.The model is applied to actual tunnel.The research concludes that the results of SPA are in good agreement with practical situation of surrounding rock.Also,the method of set pair analysis applied to the classification of surrounding rock is feasible and has high accuracy.SPA is simple and has strong maneuverability,which is a good method for surrounding rock classification.