Polymer coated quartz crystal microbalance ( QCM) sensor based on the frequency shifts due to the adsorption of compounds at the surface of modified quartz crystal electrode is an effective method for detection of sarin (GB) which is a highly toxic nerve warfare agent. A new fluorosiloxane polymer has been synthesized through 6 steps from trifluoromethyl benzene. The synthesis was achieved from trifluoromethyl benzene through nitration, hydrogenation. The obtained m-nitrotrifluoromethyl aniline was treated with NaNO2, and then hydrolyzed to m-nitrotrifluoromethyl phenol. m-nitrotrifluoromethyl phenol was reacted with allyl bromide to the ether product. The product was rearranged by Claisen rearrangement, and then reacted with polymethylhydrosiloxane under catalyst of Pt/DVTMS. The fluorosiloxane polymer can be obtained.The polymer has been successfully used as QCM coating material.