Abstract: The influence of foundation pit excavation on the displacement of adjacent tunnel has been a hot and difficult issue in the geotechnical engineering. In order to predict the displacement of lateral tunnel induced by foundation pit excavation, the dimensionality of the influencing factors on the displacement of lateral tunnel is reduced and the principal components of that are obtained based on the Principal Component Analysis（PCA）. Then, the relationship between the principal component with low-dimensional and the displacement of lateral tunnel is established using Multiple Linear Regression（MLR）. Lastly, the accuracy of PCA-MLR prediction model is verified based on the actual projects. The results show that the coupling effect of the high-dimensional influencing factors on the displacement of lateral tunnel induced by foundation pit excavation was considered. Besides, the low-dimensional principal components were used to established the MLR model. The maximum horizontal and vertical displacement of lateral tunnel induced by foundation pit excavation were predicted using PCA-MLR model. The relative error between predicted and monitoring values were less than 10%, indicating the accuracy and applicability of the developed model.