A power plant mount system with controllable damping characteristics in a broader frequency range is very important for active isolation. The operation principle and damping characteristics of a magneto-rheological (MR) semi-active mount in squeeze mode are analyzed. A vertical vibration isolation model of a power plant is proposed. A fuzzy adaptive control (FAC) system utilizing a scale factor self-turning algorithm is designed to decrease the vertical excitation force of the power plant in different operation states. A revised skyhook control strategy is also adopted to dissipating the energy by restraining the vibration of the power plant. An experimental isolation system of one real power plant is presented. The isolation test in different conditions is carried out. Experimental results show that the MR mount system can decrease the absolute force transmissibility ratio to 25%, which is better than that of rubber mounts at lower rotating speed. Test confirms that FAC，which considers vibration transmissibility and excitation frequency, can provide better performance in reducing the total vertical transmitted force than skyhook controller, which is used on vibration isolation by restraining the vibration energy of the power plant .