Abstract: Large deformation on the tunnel top and adjacent slope occurred during the face excavation construction of left line of Yuanyanghui tunnel on Shanping express highway, with maximal displacement of 34 cm monitored on site.Based on the analysis of tunnel construction process, site monitoring was carried out to the tunnel and adjacent slope, relevant theory and method were applied to investigate the inducement of its unfavorable deformation caused by excavation of tunnel opening, and control measures were also proposed according to monitoring analysis results.The face excavation construction under the control measures was analyzed by numeral simulation, it turned out to be reasonable.