Objective To observe clinical efficacy and safety of Yaotongning Capsule（ YTN） treating lumbar osteoarthritis of cold-dampness and blood stasis type. Methods Totally 108 patients with lumbar osteoarthritis of cold-dampness and blood stasis type were randomly divided into YTN high dose group

YTN low dose group and Bitongning Capsule（ 痹痛宁胶囊

BTN） group

with 36 cases in each group. The YTN high dose group took 6 YTN every time

once a day. The YTN low dose group took 4 YTN every time

once a day. The BTN group took 2 BTN

2 times per day. All groups were treated for 4 weeks. Before treatment

on the 14 th and the 28 th treated day

visual analogue scale（ VAS） and Oswestry disability index（ ODI） were used to grade degree of lumbar pain of patients. We also evaluated clinical efficacy and safety. Results The total efective rate was 85. 71% in the YTN high dose group

83. 33% in the YTN low dose group and 75. 00% in the BTN group. Clinical efficacy in the YTN high and low dose group was obviously superior to the BTN group. ODI score of the YTN high dose group treated for 14 days significantly decreased in comparison to that before treatment（ P < 0. 05）. VAS score of rest and activity pain and ODI score of each group treated for 28 days significantly decreased in comparison to that before treatment and treated for 14 days（ P < 0. 05）. VAS score of rest and activity pain of the YTN of high dose group treated for 14 and 28 days significantly decreased in comparison to that of the YTN low dose group and the BTN group（ P < 0. 05）. ODI score of the YTN of high dose group treated for 28 days significantly decreased in comparison to that of the YTN low dose group and the BTN group（ P < 0. 05）. Each group had no obvious adverse reactions. Conclusion YTN can treat lumbar osteoarthritis of cold-dampness and blood stasis type by effectively relieving the waist pain of patients and improving the function of the waist

with less adverse reaction.