Objective: To explore the pharmacokinetics of sinomenine hydrochloride by using microdialysis method. Method: The microdialysis probe was introduced to right ventricle of rats as sampling tools for real-time and in vivo collecting samples after intramscular injection. The dialysate samples were determined by HPLC. After the dialysate concentration was calibrated, the blood-drug concentration was fitted with compartment and noncompartment model. Result: The results shows that physiological disposition of Sinomenine Hydrochloride was fitted to first order rate and open one-compartment model. The main pharmcokinetics parameters were as following: Cmax 3.127 mg·L-1,Tmax 101 min,MRT 191 min. Conclusion: The pharmacokinetics characteristics of Sinomenine Hydrochloride was collected by using microdialysis method which could been selected as study tool.