Objective To explore the clinical efficacy of traditional Chinese medicine (TCM) fumigation and washing for the treatment of knee osteoarthritis (KOA). Methods Sixty patients with KOA were randomly and equally divided into treatment group and control group. The control group was given celecoxib capsules by oral administration, while the treatment group received TCM fumigation and washing combined with celecoxib. Before and after 1, 2, and 3 weeks of treatment, the degree of knee pain and knee function in the two groups were evaluated using the visual analogue scale (VAS) and Lysholm score, respectively. Results Before and after 1, 2, and 3 weeks of treatment, both groups had significantly reduced VAS scores and significantly increased Lysholm knee scores over time (P<0.05). After 1 and 2 weeks of treatment, there were significant differences in the VAS score and Lysholm knee score between the treatment group and the control group (P<0.05). Conclusion TCM fumigation and washing can relieve knee pain and improve knee function in patients with KOA.