To investigate the analgesic effect of tetrandrine(TEF) on chronic inflammatory pain induced by Freund's complete adjuvant(FCA) in mice.Methods:A FCA plantar chronic inflammatory pain model was established，and TEF was used to conduct intervention treatment.The analgesic effect of TEF was determined by pain behavioral tests of mechanical stimulation，thermal radiation stimulation，hot-plate test，and nociceptive response.Real-time quantitative polymerase chain reaction(real-time PCR)，Western blot and other methods were used to detect the messenger ribonucleic acid(mRNA) and protein expression changes of transient receptor potential vanilloid-1(TRPV1)，and to explore the regulatory pathway and mechanism of TRPV1 sensitization.Results:The model of chronic inflammatory pain in mice was obtained.TEF significantly increased the pain thresholds of mechanical stimulation and thermal radiation stimulation in mice，but did not affect the pain threshold of hot plate stimulation and the weight of mice.Compared with the control group，TRPV1 in the mice with FCA-induced chronic inflammatory pain was significantly reduced after the intervention of TEF(P<0.05).Conclusion:TEF significantly inhibited the production of TRPV1 in the mice with FCA-induced chronic inflammatory pain，and had analgesic effect on chronic inflammatory pain.No tolerance or toxicity of TEF has been found.