Taking Xiaohe～Ankang section of Baotou～Maoming highway as project case, the authors expatriate on the design concepts and construction methods of "zeroexcavation" of tunnel portal construction in different terrains and geological conditions so as to set up the new concept of harmonic development between the construction of the highway infrastructure facilities and the protection of the environment so that the ecological environment can be properly utilized and protected and the adverse impact of the construction activities, such as the tunnel portal slope cutting, on the natural ecology can be minimized. The paper can provide reference for the design and construction of highway tunnels in the future.