Taking the treatment of the karst caves encountered during the construction of new Dabashan tunnel as an example, the authors briefly present the treatment scheme for karst caves and the reinforcement method for pile tundations. The authors make further discussion on the treatment technology for large scale fillingtype karst caves in terms of advance reinforcement by large pipe roof, radial grouting through small pipes, steel pipe pile and jet grouting pile. This paper can provide reference for similar projects in the future.