【Abstract】 Objective To explore the curative effect of arthroscopic debridement (AD) combined with proximal fibular osteotomy (PFO) on medial knww osteoarthritis. Method A total of 25 knee osteoarthritis (KOA) patients in Kellgren-Lawrecne Stage II and III who were hospitalized in Suzhou Hospital affiliated to Anhui Medical University from July, 2017 to July, 2019, and conformed to inclusion criteria were selected and divided into: group A (control group): 12 cases, accepting AD treatment; group B (test group): 13 cases, accepting AD combined with PFO. Visual analogue scale (VAS) of pain, knee score scale of the Hospital for Special Surgery (HSS) in US and femoral tibial angle (FTA) of the patients in the two groups before the operation and one week, three months and one year after the operation, respectively, were compared. Results The comparative differences between the two groups in basic conditions and related preoperative indexes were not statistically significant (P＞0.05); VAS scope of patients in group A was lower than that in group B after the operation, and VAS scores of patients in group A were higher than those in group B three months and one year after the operation, and the differences were of statistical significance (P＜0.05); HSS scores in both groups after the operation were higher than those after the operation, where the HSS scores in group A one week and three months after the operation were lower than those in group B, and the difference was of statistical significance (P＜0.05); FTA in group A increased from (183.19±0.73) before the operation to (183.30±0.69) one year after the operation, and the difference was statistically significant (P＜0.01); No serious complications occurred to patients in both group A and group B. Conclusion AD combined with PFO can be used to treat early and middle-stage KOA and improve line of force of knee joint. With high safety and effectiveness, it can achieve better effect than pure AD.