To compare the efficacy difference between fire acupuncture with centro-square needles (FACSN) and filiform needling (FN) for knee osteoarthritis (KOA).
Seventy-two patients were randomly assigned into an FACSN group and an FN group, 36 cases in each one. 
Compared before treatment, the score of VAS and the total score of WOMAC were improved in the two groups at each time point after treatment (all 
Fire acupuncture with centro-square needles has relatively high cured and remarkable effective rate for KOA, with rapid onset; as for pain relief, the efficacy is superior to filiform needling.