OBJECTIVE： To observe the efficacy and safety of fluorouracil combined with paracetamol in the treatment of knee osteoarthritis and its effects on related indexes. METHODS： Totally 115 patients with knee osteoarthritis admitted to our hospital from March 2015 to March 2018 were divided into control group （57 cases） and observation group （58 cases） according to medication plan. Control group was given Paracetamol tablets 0.3 g orally， 3 times a day， for consecutive 8 weeks. Observation group was additionally given intra-articular injection of Fluorouracil injection 0.075 g on the basis of control group， once a week， 4 times as a treatment course， for 2 courses in total. Clinical efficacies， VAS scores， Lysholm knee scores， Fugl-Meyer Assessment （FMA） scores， Barthel indexes， WHO QOL-BREF scores before and after treatment and the occurrence of ADR of 2 groups were observed. RESULTS： The total response rate of observation group was 94.83％， which was significantly higher than 78.95％ of control group （P＜0.05）. Before treatment， there was no statistical significance in VAS score， Lysholm knee scores， FMA scores， Barthel index or QOL-BREF scores between 2 groups （P＞0.05）. After treatment， VAS scores of 2 groups were significantly lower than before treatment， and the observation group was lower than the control group； Lysholm knee scores， FMA scores， Barthel indexes and QOL-BREF scores were significantly higher than the same group before treatment， and observation group was significantly higher than control group （P＜0.05）. There was no statistical significance in the incidence of ADR between 2 groups （P＞0.05）. No severe ADR was found in 2 groups during treatment. CONCLUSIONS： Fluorouracil combined with paracetamol can significantly improve therapeutic efficacy of patients with knee osteoarthritis， and can significantly improve knee function， motor function， self-care ability and quality of life without increasing the occurrence of ADR.