To observe the curative effect of dissolving phlegm-stasis on knee osteoarthritis. Methods: The 100 patients with knee osteoarthritis were randomly divided into two groups. The 50 patients in the treatment group orally took Chinese medicine while the other 50 patients in the control groups orally took Votalin and Vitamin C for one week as a course of treatment. At the end of 2-week treatment, analytic comparison was carried in evaluate the curative effect and the changes in total score of symptoms before and after treatment between the two groups. Results: The total score of symptoms after treatment was significantly lower than that before treatment in both groups (P<0.01, P<0.05). The total score after treatment of patients with X-ray grade Ⅰ and Ⅱ in the treatment group was more obviously reduced as compared to the control group (P<0.05).The remarkably effective rate after treatment of patients with X-ray grade Ⅰ and Ⅱ in the treatment group was also higher than that in the control group (P<0.05). Conclusion: The treatment of knee osteoarthritis with dissolving phlegm-stasis can effectively improve the clinical symptoms.