以正在建设中的包（头）茂（名）高速公路小河-安康段为依仗，详细论述了隧道进洞施工“零开挖”在不同地形、地质条件下的设计理念和施工方法，以企树立公路基础设施建设与环境保护全面协调发展的全新思维方式，以保护和合理利用生态环境，将工程建设（洞口开挖）对自然生态的不利影响减少到最低程度，可为公路隧道设计施工提供借鉴。

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.