Objective: The usnic acid phospholipid complex was prepared and characterized. Method: The complex was prepared by solvent reaction method.Taking recombination rate and content of usnic acid as index

the preparation process parameters of the complex were optimized by single factor tests and orthogonal test.The oil/water partition coefficient of this complex was determined and the structure of the complex was characterized by ultraviolet spectroscopy(UV)

Fourier transform infrared spectroscopy(FT-IR)

stereomicroscope and scanning electron microscope(SEM). Result: The optimal preparation conditions were as follows:the drug concentration of 10 g·L-1

usnic acid-phospholipid(1:1)

reaction time of 5 h and reaction temperature of 50℃.The recombination rate of the complex prepared under these optimized conditions was 86.85%

and the content of usnic acid was 38.46%.The logarithm value of oil/water partition coefficient was 2.35.UV

FT-IR

stereomicroscope and SEM analysis showed that the complex had been formed. Conclusion: This optimized preparation technology in this research is stable and feasible

it can provide conditions for further study of usnic acid.