With the progress of civilization, buildings and residential constructions become taller and taller. Seismic design for buildings to resist earthquakes also attracts more attentions. The common vibration energy dissipation devices such as TMD, TLD, etc. have been popular but they have limitations such as requirement for large space to install and difficult to be installed after the building is finished. TLCD as an alternative may improve these defects. The new developed MR-TLCD system has the advantages of real-time control and is reversible. Based on the theorem of TLCD, the control equation of MR-TLCD considered the fluid viscosity. The parameters of external control magnetic force and properties of MR-fluid inside the tube needed in damping ratio calculation were measured in the experiment, where a model free vibration experiment was performed. A MR-TLCD system of which the damping ratio was designed in harmony with optimal damping ratio. The comparison was also made for the damping effect of traditional TLCD, MR-TLCD(uncontrolled), MR-TLCD(passive controlled) under dynamic loadings of various frequencies and amplitudes. The experimental results showed that MR-TLCD is more suitable in large amplitude external force. TLCD plays the best vibration mitigation effect when the external force is resonant to the structure, but MR-TLCD is better in other frequency range. It is encouraging that the application of MR-TLCD can have larger scope than TLCD. Keyword: vibration mitigation, experiment, TLCD, MR-TLCD