OBJECTIVE:To optimize the formulation of nanostructured lipid carriers loaded with lornoxicam (LN-NLC). METHODS:Emulsification-solvent evaporation method was used to prepare the LN-NLC. Using drug-lipid ratio,dosage of soy lec-ithin,liquid-lipid ratio (proportion of liquid lipid to total lipid) and dosage of emulsifier as factors,the overall normalized value was calculated by particle size,Zeta potential and entrapment efficiency as indexes was used as comprehensive index. Central com-posite design-response surface method was used to optimize the formulation and investigate the appearance and stability of prepared LN-NLC. RESULTS:The optimal formulation were as follows as drug-lipid ratio of 1:50,dosage of soy lecithin of 162.5 mg,liq-uid-lipid ratio of 25% and emulsifier dosage of 958.2 mg. The particle size of prepared LN-NLC was(96.9±3.3)nm,Zeta poten-tial was(-16.1±0.3)mV,entrapment efficiency was(60.1±0.9)%(n=3),which showed relative error of 2.47%,-4.55%,-0.17%with predicted value,respectively. The prepared LN-NLC was spherical. It had no obvious changes in particle size and Ze-ta potential in sealed storage for 30 d in 4 ℃,and the entrapment efficiency only declined 1.2%. CONCLUSIONS:The LN-NLC formulation is successfully optimized,and the LN-NLC has good stability.