Objective To compare the clinical efficacy of rhomboid block and peripheral nerve block of knee joint and their combined treatment for knee osteoarthritis. Methods 92 patients with knee osteoarthritis were randomly divided into 3 groups，29 patients in group A（knee peripheral nerve block group），32 patients in group B（rhomboid block group）and 31 patients in group C（knee peripheral nerve block combined with rhomboid block group）.Visual analogue scale（VAS）and Lysholm Scale were performed before treatment and at 3 d，7 d，1 month and 6 months after treatment，and the pain relief rate and knee rehabilitation remission rate were compared. The ratio of the second and third treatments were compared，and adverse reactions during treatment and follow-up was recorded. Results In group A，the VAS and Lysholm scores within 1 month after treatment were significantly different from those before treatment（P < 0.05）；The VAS and Lysholm scores of group B and group C at each time point after treatment were significantly different from those before treatment（P < 0.05）；7 days after treatment， the pain relief efficiency and knee rehabilitation relief efficiency in group B and C were significantly higher than that in group A（P < 0.05）；The ratio of the second and third treatments of group C were significantly lower than those of group A and B（P < 0.05）；No obvious adverse reactions were observed in the 3 groups. Conclusion Peripheral nerve block combined with rhomboid block is more effective in the treatment of knee osteoarthritis with⁃ out obvious adverse reactions.