The characteristics and effectiveness of double tuned mass dampers (DTMD) have been studied by many researchers. DTMD usually consists of one larger mass block and one smaller mass block. In this study, DTMD was proposed to reduce the vibration of vertical pumps in industrial plants. In order to assess the efficiency of the proposed method, numerical analysis for the simplified vertical pump model with single and double TMDs was carried out. It was also investigated that the effects of optimal TMD parameters such as frequency ratio and damping ratio on dynamic responses of the main structure. According to analysis results, DTMD are more effective to control the vibration of the vertical pump and show good robustness to the change in the stiffness of TMD.