With the further improvement of the requirements for aircraft reliability and comfort, the vibration isolation problem of aircraft powerplant has become a hot research topic both domestically and internationally in recent years. The installation system of the aircraft powerplant is the main component for vibration isolation and noise reduction, and the damping rubber material is the core functional material of it. Silicone rubber is the first choice in aerospace industry due to the excellent performance at unusually low temperatures, high thermal stability, mechanical stability in wide temperature range. From the analysis of fatigue mechanism of rubber materials, a series of researches have been carried out mainly on Vinyl and Hydrogen containing Silicone oil contents of Silicone rubber in this article, and the excellent fatigue performance material, MK5200Q, is obtained. Comparing with traditional Silicone rubber, tear strength of the MK5200Q material increases 2.03 times and tension strength 1.73 times and elongation 1.37 times. The damping property of the material is excellent and the damping factor is 0.1912 at room temperature. The rubber component made of MK5200Q of the APU vibration isolator is quite good after the fatigue tests. Demonstration tests of the vibration isolators made of the material have passed under the witness of appraisal agency.