Abstract: With an example of simply supported beam, it is presented to active control structure-borne sound by mean of radiation modes. The radiation efficiency of the radiation modes falls off very rapidly with the increase of modes order at low frequency. A new control strategy is developed in which the adjoint coefficient of the first L radiation modes measured by using shaped PVDF sensor, then the sound powers of the first L radiation modes are minimized. Finally,by numerical calculation the control effects of number of control forces and sensors are investigated.