DaliLijiang highway is located in the northwest of YunnanGuizhou Plateau with the lacustrine soft soil ground. The gravel pile composite foundation is adopted to increase the bearing capacity of the lacustrine soft soil ground. The field application of gravel pile foundation in the southwest highway soft ground treatment is discussed and studied. The basic features of lacustrine soft soil along the highway are investigated using the field and laboratory test data. Then，the effect of gravel pile on the bearing capacity of natural lacustrine soft ground is evaluated based on the field monitoring data. The "Composite modulus homogenization" and "typical pile group element method" are adopted for the simulation of gravel pile foundation in lacustrine soft ground based on FLAC3D. Simulation results show that under the flexible foundation of highway，the use of crushed stone composite foundation with crushed stone cushion is effective to improve the bearing capacity of deep soft ground.〖KH*2D〗