Abstract: A model based on normal cloud model and Projection Pursuit Analysis has been established to forecast rockburst intensity of large deep buried diversion tunnels. Based on comprehensive analysis of the related influential factors on the rockburst, we select 4 factors as the assessment indicators for the intensity evaluation, including the elastic strain energy index, the ratio of uniaxial compressive strength to tensile strength, the ratio of tangential stress to uniaxial compressive strength, and the rock brittleness index. The corresponding assessment standard are determined by the given indicators, and the weights of indicators are calculated based on Projection Pursuit Analysis, finally, the certainty degree of each indicator is calculated by normal cloud generator and the cloud graph is given. Combining with 7 deep buried tunnel cases, the forecasted results are compared with those of other prediction methods, which shows that the presented method can obtain accurate results.