The theory of Chinese medicine meridian Qi-blood has a close correlation with human skin microcirculation. To explore the mechanism of moxibustion acting on human microcirculation and obtain more accurate detection results of moxibustion effect, a non-invasive detection method based on optical coherence tomography imaging was proposed. Moxibustion experiments were carried out on 10 healthy volunteers at the Laogong and Daling Point. The changes of OCT backscattered signals at the skin of different acupuncture points were directly observed. Based on the single scattering model of the OCT signal, the A-SCAN at the acupoint is fitted to obtain the attenuation coefficient of the acupoint skin. The results showed that within 30 minutes after moxibustion, compared with other acupoints on the hand, the intensity of the backscattered signal was decreased about 5 dB in the depths of 0.5-2mm at the skin of acupuncture points of the same meridian. The attenuation coefficient increased significantly over time and reached a peak then decreased. At the peak, the attenuation coefficient increased to twice that before experiments. The optical coherence tomography system can directly reflect the changes of skin microcirculation, and further validate the theory of traditional Chinese medicine meridian Qi and blood. This method can effectively detect the physiotherapy effect of moxibustion.