Abstract: OBJECTIVE To observe the clinical efficacy difference of the thunder-fire moxibustion combined with celecoxib for knee osteoarthritis (KOA) before and after the treatment. METHODS Forty five patients with KOA were randomly divided into the celecoxib-intervened first group and the thunder-fire moxibustion-intervened first group. The celecoxib-intervened first group was treated by celecoxib for two weeks， then treated by thunder-fire moxibustion for another two weeks after one week of elusion， and the thunder-fire moxibustion-intervened first group was treated conversely. Four weeks' follow-up was performed for both groups after the treatment. The degree of tenderness， swelling， activity and WOMAC function score of knee joints were observed before and after the treatment. RESULTS After two weeks of treatment， the degree of tenderness， swelling and activity of knee joint in two groups improved significantly (P<0.05)， and WOMAC function total score also decreased (P<0.05). The degree of tenderness and swelling， activity improvement of the knee joints in the thunder-fire moxibustion-intervened first group were better than those of the celecoxib-intervened first group (P<0.05)， and WOMAC total score decreased more significantly than that of the celecoxib-intervened first group (P<0.05). After one week of elution， there was no significant improvements of the four aspects in the celecoxib-intervened first group， while the improvements of the above four aspects in the thunder-fire moxibustion-intervened first group were significantly different compared with pre-treatment (P<0.05). During the follow-up period of the end of the treatment the degree of tenderness， swelling and activity of knee joints in both groups were significantly improved than those of the pre-treatment (P<0.05)， and WOMAC total score decreased significantly than that of the pre-treatment (P<0.05). But there was no significant difference between two groups. CONCLUSION Thunder-fire moxibustion and celecoxib can improve the joint tenderness， swelling， activity and dysfunction of KOA patients， but the thunder-fire moxibustion shows more advantages in improving KOA patients' joint tenderness， swelling， activity and other functions. The combination of thunder-fire moxibustion and celecoxib shows similar effects no matter which one is used first.