To analyze the mechanism of the treatment of knee osteoarthritis (KOA) with drug canister acupuncture based on the changes of metabolomics in synovial fluid.Methods:A total of 98 patients with KOA admitted to Bao'an Traditional Chinese Medicine Hospital Group from April 2018 to May 2019 were selected as the research objects,and were divided into a control group (n=52) and an observation group (n=46).The control group was treated with Western medicine,and the observation group was treated with drug canister acupuncture therapy.VAS scores and WOMAC scores of all patients before and after treatment were compared.Blood uric acid,C-reactive protein and erythrocyte sedimentation rate before and after treatment were calculated.NMR analysis was performed on the joint fluid isolated from the knee joint.Results:Before treatment,there were no statistical differences in VAS and WOMAC scores,serum uric acid,C-reactive protein and erythrocyte sedimentation rate between the drug canister acupuncture therapy group and the Western medicine treatment group (P>0.05).After treatment,the VVAS and WOMAC scores,the content of serum uric acid,C-reactive protein and erythrocyte sedimentation rate in both groups decreased,and the treatment of drug canister acupuncture was decreased more sharply (P<0.05),which indicated that the drug canister acupuncture was more effective in treating KOA.After treatment,isobutyric acid and glucose increased,and hydroxyproline,asparagine,serine and uridine decreased in the drug canister acupuncture therapy group and the Western medicine treatment group (P<0.05).Conclusion:By detecting metabolomics changes of joint fluid,drug canister acupuncture therapy can effectively improve the therapeutic effects and body function of patients with KOA.