Abstract: During the operation of the emergency diesel generator in the Daya Bay nuclear power station,the vibration of the generator will cause strong vibration of the cooling pipes connected to it,which brings potential safety hazard to the normal operation of the generator.In order to discover the feasibility of the method to reduce the vibration level of the cooling pipe by attaching Dynamic Vibration Absorber（DVA） on it,the simulation and optimal design of the method was carried out.At first,the computational model of the cooling pipe was set up by finite element method.The response,which was measured from the experiment on site,was applied on the model of the cooling pipe as an excitation to compute the total response of the whole cooling pipe.Based on the result of the computation,the parameters of the DVA used to reduce the vibration of the pipe were determined.Then the optimal procedure was carried out to decide the best mount position of the DVA on the pipe,during which the vibration response of the key position of the cooling pipe was chosen as the optimal goal.The result of the simulation verified the validity of the vibration control method.