Abstract: A new seepage analysis program for concrete dams is developed with the help of the interface between Marc, a commercial finite element software, and Fortran, including the techniques of inactive/active element and local closing element. According to the observed data of uplift piezometric water head, the permeability coefficients of a concrete gravity dam body and its foundation are inversed by a developed genetic algorithm. Calculation results show that the approach of inverse analysis on the permeability coefficients of a concrete dam is feasible and efficient.