In order to explore the active mechanisms of meloxicam and lysozyme, the interaction between the molecules of rheumatoid arthritis drugs, meloxicam and lysozyme was studied using fluorescence spectroscopy, synchronous fluorescence spectroscopy and theoretical modeling analysis under the pH=7.40 experimental conditions. The results showed that meloxicam was able to effectively quench the endogenous fluorescence of lysozyme, forming a 1∶1 complex and changing the conformation of lysozyme. Thermodynamic results indicated that the main type of meloxicam-lysozyme system was a hydrophobic interaction. The results of theoretical modeling indicated that the system had hydrogen bonds in addition to hydrophobic interactions and that meloxicam was surrounded by the active amino acid residues Glu35 and Asp52 from the lysozyme, which changed the microenvironment of amino acid residues at the active center of the lysozyme. When a patient took meloxicam 15 mg, the protein binding rate of meloxicam to lysozyme W(B) was 3.71%~8.79%, indicating that the combination of meloxicam and lysozyme has little effect on anti-inflammatory and antibacterial function of lysozyme itself, and the system drug binding rate W(Q) was 1.08%~1.14%, indicating that the combination of lysozyme and meloxicam does not affect the efficacy of meloxicam. This study theoretically proved that lysozyme does not have a serious effect on its own function or the efficacy of meloxicam after it is combined with meloxicam in plasma.