The local slope sliding would occur to portal section of unsymmetricallypressured tunnel when carrying out cover arch construction. Hence, 3 slope reinforcement schemes are proposed and comparatively analyzed. The slope safety factor, total slope displacement, effective plastic strain, maximum shear strain and vertical ground displacement are analyzed by calculation modeling based on finite element strength reduction method. The comparison results and displacement monitoring results show that: (1) The slope reinforcement scheme of anchor bolt support + local steel pipe grouting + net spraying support is superior to other two schemes. (2) The scheme adopted can improve the stability of the slope, maximally reduce the influence of tunnel excavation on ground deformation, and achieve good social and economic benefits.