A new frequency conversion TMD(tuned mass dampers) semi-active actuator system for structural vibration control was proposed. By means of the genetic algorithm toolbox, the dynamic magnification factor of the structure was analyzed and the feasibility and effectiveness of the TMD system to the structural vibration control was proved. The results show that single frequency conversion-TMD as a semi-active drive can effectively reduce the structure reaction, and it has a wider vibration frequency bandwidth and better control effect compared with the traditional TMD.