An improved subsurface drainage system was tested in Huaibei plain, China to address flooding and land shortage issues. By adding high permeability materials above drains, the system increased drainage efficiency compared to traditional methods. Field experiments showed the improved system discharged 1.9 times more water than conventional drainage. Numerical simulations confirmed the system lowered water tables faster, benefiting crop growth. The improved drainage reduced surface runoff and soil water storage after rainfall, improving overall drainage effectiveness. This research provides a scientific basis for designing and implementing improved subsurface drainage systems in agricultural settings.