Objective  To prepare and characterize oridonin phospholipid complex.    Methods  Oridonin phospholipid complex was prepared by solvent evaporation. The thermodynamic properties of oridonin phospholipid complex were studied by differential scanning calorimetry. The state of oridonin in the complex was studied by X-ray diffraction. Whether new chemical bonds existed were studied by UV-VIS spectrophotometry. The dispersion of oridonin phospholipid complex in water was studied through observing crystals of oridonin by microscopy.    Results  The peak of melting point changed in the DSC spectra. The crystallogram showed that oridonin dispersed in an amorphous form in phospholipid

meanwhile the peaks of crystal diffraction disappeared. There was no new chemical bonds appearance. The oridonin phospholipid complex was instable and could easily separate crystals out in water.    Conclusion  We successfully prepare oridonin phospholipid complex

but the system is instable in water

so can not be used as drug delivery system for oridonin alone.