Objective To observe the effect of moxibustion at Shenque(RN 8) and Guanyuan(RN 4) on the skin temperature of Ren meridian and its left and right sides of subjects with Yang deficiency constitution, and to explore the mechanism of moxibustion on Yang deficiency constitution. Methods 31 subjects with Yang deficiency constitution were randomly divided into control group (n=15) and moxibustion group (n=16). The control groupreceived health propaganda, and the moxibustion group received health propaganda and moxibustion at Shenque (RN 8) and Guanyuan (RN 4). Before and after the intervention, the skin temperature of acupoints on the Ren meridian, the average skin temperature of Ren meridian（thoracic and abdominal segment） and its left and right 1.5-inch sides were recorded by infrared thermal imager. Results 1. Compared with pre-intervention, the average skin temperature of Ren meridian（thoracic and abdominal segment） and its left and right sides in the moxibustion group increased significantly（P<0.05, P<0.05）, the average skin temperature of Ren meridian was higher than that of its left and right sides（P<0.05, P<0.01）, and the average temperature of left side was significantly higher than that of right side(P<0.05); There was no significant difference in the control group before and after intervention. 2. Compared with pre-intervention, the skin temperature of Tiantu(RN 22）（P<0.05） and Danzhong (RN 17)(P<0.05) on the Ren meridian in the moxibustion group increased significantly, while the skin temperature of Zhongwan（RN 12） and Qihai（RN 6） increased, but there was no significant difference. There was no significant difference in skin temperature of acupoints on Ren meridian in the control group before and after intervention. 3. Before the intervention, the temperature of acupoints on the Ren meridian in the two groups both decreased gradually in a downward direction. After the intervention, the temperature of acupoints of Ren meridian in the moxibustion group increased, and the acupoints of the thoracic segment of Ren meridian was more significant. On the whole, it was still showed the trend of heat in the upper and cold in the lower. Conclusion Moxibustion at Shenque (RN 8) and Guanyuan (RN 4) can increase the skin temperature of Ren meridian and its left and right sides，and play a integral role in regulating the body temperature , but it has not changed the trend of heat in the upper and cold in the lower in the short term; The difference of warming degree between Ren meridian and its adjacent parts that caused by the moxibustion at Shenque （RN 8） and Guanyuan （RN 4） may be related to the relative yin-yang attribute of each part.