The uniaxial saturated compressive strength data of the surrounding rock of the sample group obtained by on-site sampling, the average value and standard deviation of the sample group data are further calculated, and the standard deviation of the sample group data is divided by the average value to obtain the coefficient of variation of the sample group data. After using the statistical formula, the correction standard value of the surrounding rock saturated compressive strength of the sample group data is calculated, and the influences of groundwater, main weak structural surface occurrence and initial stress state are considered, and the BQ value of the basic quality index of the rock mass is calculated. The correction is carried out to obtain the correction value of the basic quality index [BQ] of the rock mass. Based on the qualitative characteristics of the rock mass, the comprehensive evaluation of the surrounding rock is carried out to determine the detailed classification of the surrounding rock, so as to establish the dynamic design system of the surrounding rock of the tunnel.