Using 1-bromo-3-fluorobenzene、4-bromobenzonitrile、1-(trans-4-propylcyclohexyl)-1-chloro-methane etc as starting materials, 2,6 - difluoro-4 - [3 - fluoro-4'-[1 - methyl - 2 - (4 -propylcyclohexyl) - ethyl]-biphenyl]phenyl difluoromethoxy-3, 4,5 - trifluorobenzene was synthesized by a method consisting of seven steps: Grignard reaction、Suzuki reaction、Witting reaction、hydrogenation reaction, etc. The reaction solvent of grignard reagent and 4-bromobenzonitrile was xylene；the optimum reaction time of lithiation reaction was 2h . The overall yield was about 30% and the purity reached 99.7%（GC）（mp：82.97-85.04℃）. Adding the compound into base composition of liquid crystal can improve the birefringence （Δ n），reduce the threshold voltage（Vth）.