南岭隧道因岩溶病害严重，在施工阶段即成为工程难点，施工完成后就开始整治，由于埋深较浅，地下水与地表水联系紧密，加上京广线铁路运输繁忙，历次整治均不能彻底清除病害。介绍了南岭隧道地质条件、原设计及施工概况，以及隧道病害现状及本次病害整治措施。同时对隧道选线设计提出了一些建议。

 Due to the presence of karsts, Nanling tunnel is one of the difficult tunnels even during the construction stage. Soon after the completion of the tunnel, the treatment of the defects of the tunnel begins. Due to the shallow cover of the tunnel, the close circulations between the ground water and surface water and the busy traffics of the BeiingGuangzhou railway, the defects of the tunnel can not be completely eliminated in the several treatment campaigns. The article introduces the geological conditions, design and construction, present situation of the defects and the defect treatment measures of Nanling tunnel. The article also provides some recommendations on the alignment determination of other tunnels in the future.