Abstract： Objective： To observe the clinical effect of the external application of Gutong plaster combined with oral administration of Celecoxib capsules for knee osteoarthritis(KOA) at attack stage. Methods： A total of 100 cases of KOA patients at attack stage of cold-dampness stasis and stagnation type were divided into the control group and the observation group，50 cases in each group. The control group was given the oral administration of Celecoxib capsules and the external application of diclofenac sodium gel. The observation group was given the oral administration of Celecoxib capsules and the external application of Gutong plaster. Both groups were treated for four weeks. Before treatment and on the 7th，14th and 28th days after treatment，in the two groups，the scores of Visual Analogue Scale of pain(VAS) in resting period were compared with those in active period. Before treatment and after four-week treatment，the scores of pain-related symptoms，scores of the Western Ontario and McMaster Universities Osteoarthritis Index(WOMAC) Scale，scores of cold-dampness stasis and stagnation syndrome，and scores of the Arthritis Measurement Scales 2-Short Form(AIMS2-SF) were evaluated. The clinical effect in the two groups was compared. Results： After treatment， the clinical effect in the observation group was better than that in the control group(P＜0.05). In the two groups，the VAS scores in resting period and those in active period after treatment were gradually decreased(P＜0.05)； on the 7th， 14th and 28th days after treatment， the two scores in the observation group were lower than those in the control group(P＜0.01). The scores of pain- related symptoms， scores of WOMAC Scale， and scores of cold- dampness stasis and stagnation syndrome in the two groups were decreased when compared with those before treatment(P＜0.01)，and AIMS2-SF scores were increased(P＜0.01). The scores of pain-related symptoms， scores of WOMAC Scale， and scores of cold- dampness stasis and stagnation syndrome in the observation group were lower than those in the control group(P＜0.01)，and AIMS2-SF score was higher than that in the control group(P＜ 0.01). Conclusion： The external application of Gutong plaster combined with oral administration of Celecoxib capsules can significantly alleviate the degree of pain in the knee joint and pain- related symptoms of KOA patients at attack stage，and improve function of the knee joint and their quality of life，with defined clinical effect.