Abstract: Objective To establish a method to implant the microdialysis probe into rabbit’s knee joint capsule, and apply the method for pharmacokinetics study in knee joint fluid of rabbit. Method The microdialysis probe were implanted in rabbit’s knee joint capsule with the help of syringe needle and guide catheter, and the position of the probe was verified by X-ray. Sinomenine was subject in the pharmacokinetics study, HPLC-MS was used to test the drug concentration in blood and knee joint fluid. Results The membrane window of the microdialysis probe was in rabbit’s knee joint capsule, and the method to implant the microdialysis probe was applied for pharmacokinetics study successfully. Conclusion The method to implant the microdialysis probe was established, and microdialysis has evident advantages in pharmacokinetics study.