Based on the solid model potential fluid model and the flow structure coupling model creates and calculation, this paper focus on study the damping mechanism of the tuned liquid damper. First, the solid model and the potential fluid model of static analysis and frequency domain analysis are executed, after the basis of the analysis is complete, implicit dynamics calculations and analysis are executed on the flow structure coupling model. The schedule changes of the displacement at the top of building are caculated under the condition of with TLD and without TLD in a specific level of vibration loads. Calculations show that: the TLD design in accordance with building natural frequency can effectively reduce the displacement of the top of the building.