Aiming at solving scheduling problem of flexible manufacturing system, this paper puts forward a FMS scheduling problem where single AGV with two buffers system is to be considered. Such an AGV with two buffers system was replaced with double-buffer AGV system in the next content. To solve FMS scheduling problem with double-buffer AGV system, a mathematical model which integrated double-buffer AGV and jobs was designed. And an improved genetic algorithm is proposed to sequence processing of jobs and the moving path of double-buffer AGV. The experiments made in simulation FMS production line laboratory realized scheduling integration of jobs and AGV, meanwhile, experiments gained processing sequence of jobs on each machine and moving path of AGV. Contrasting results of double-buffer and no-buffer AGV system verified double-buffer AGV system has higher feasibility and effectiveness.