Abstract: Yang Yin, Lin Tong, Su Qianya, Jia Gaorong, Huang Yuqing, Fang Jing Laser Department, Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing 210042, China Corresponding author: Lin Tong, Email: ddlin@hotmail.com 【Abstract】 Objective To compare the efficacy and safety of two intense pulsed light （IPL） devices for the treatment of facial photoaging. Methods A randomized split?face clinical trial was conducted, and 30 female subjects with facial photoaging were enrolled and randomized to receive treatment with Lumenis One on one half of the face and BBL on the other facial side, once every 3 - 5 weeks for 5 sessions. Each subject was followed up before the first treatment （the first interview）, 4 weeks after the third treatment （the second interview）, 4 weeks after the fifth treatment （the third interview） and 8 weeks after the fifth treatment （the fourth interview）. During each follow?up period, global scores for photoaging （GSP） were used to evaluate the photoaging degree on the whole face, a 4?level grading method was applied to evaluate the improvement degree of 5 photoaging signs on each facial side, including wrinkles, skin texture, pigmented spots, telangiectasia and skin tightening, and the visual analogue scale （VAS） to assess pain induced by treatment. After the last treatment, self?assessment on the degree of satisfaction with therapeutic effects was conducted in subjects. Comparisons in the GSP and improvement scores between the two facial sides were conducted by repeated measures analysis of variance （ANOVA）. Results A total of 26 subjects completed all the treatments and follow?up. Evaluation of the whole face showed that the GSP significantly decreased from 3.19 ± 0.75 before the first treatment to 2.15 ± 0.83 at 4 weeks after the third treatment （P < 0.01）. At 4 and 8 weeks after the fifth treatment, the GSP decreased to 1.85 ± 0.88 and 1.85 ± 0.97 respectively, and no significant difference was observed between the two GSPs （P > 0.01）. Evaluation of each facial side showed that improvement scores of skin texture, pigmented spots, telangiectasia and skin tightening on the two facial sides all increased at first and then decreased over the treatment time （Ftime = 18.75, 10.25, 12.83, 15.73, respectively, all P < 0.05）, and the improvement scores significantly increased at 4 weeks after the fifth treatment compared with those at 4 weeks after the third treatment （all P < 0.017）. There were no significant differences in the improvement scores of skin texture, telangiectasia and skin tightening between the third and the fourth interview, but the improvement score of pigmented spots decreased slightly at 8 weeks after the fifth treatment compared with that at 4 weeks after the fifth treatment （P < 0.017）. During the whole treatment period, no evident improvement was observed in wrinkles （Ftime = 3.17, P > 0.05）, and improvement scores of 5 photoaging signs did not differ between the Lumenis One?treated side and BBL?treated side （all P > 0.05）. In addition, the VAS pain score was significantly lower in the BBL?treated side than that in the Lumenis One?treated side （4.62 ± 1.54 vs. 5.80 ± 1.74, t = 2.87, P < 0.05）. Most subjects were satisfied with the therapeutic effects （88.46%, 23/26）. Conclusion Both Lumenis One and BBL can be applied to treat facial photoaging safely and effectively, and improve signs of photoaging such as pigmented spots and skin texture, but the degree of pain on the BBL?treated side is milder than that on the Lumenis One?treated side.