To explore the infrared thermal imaging(IRTI) characteristics of the reflection regions of zang-fu organs in patients with metabolic syndrome(MS) using IRTI technology.Methods:The participants included healthy volunteers and the MS patients in the Department of Endocrinology and Inpatient Ward of South District of Guang'anmen Hospital，China Academy of Chinese Medical Sciences from August 2021 to April 2022.After strict screening，120 participants conforming to inclusion criteria and with complete experimental indexes were enrolled，with 96 in MS group and 24 in healthy control group.The average surface temperature of the regions of interest(ROIs) in the torso of the participants was analyzed.Results:The infrared thermal image of MS patients showed obvious cool deviation with uneven distribution，discontinuity，and asymmetry.Compared with those of healthy controls，the average surface temperature of epigastrium，upper abdomen，conception vessel，right waist，left waist，governor vessel and other ROIs of young MS patients was decreased(P<0.01 or P<0.05); the average surface temperature of all ROIs of middle-aged MS patients was lowered(P<0.01 or P<0.05); the average surface temperature of the ROIs of participants in different age groups presented a decreasing trend with the increase of abnormal metabolic indexes，and significant cool deviation appeared in upper abdomen and right waist.Among 11 MS patients，the average surface temperature of the ROIs was negatively correlated with waist circumference(P<0.01 or P<0.05).Conclusion:Waist circumference is a key specific index of MS.The infrared thermal image of zang-fu reflection regions in the torso of MS patients had characteristic cool deviation，especially in upper abdomen and right waist.This suggests that yang qi deficiency in spleen and kidney，reduced function of zang-fu organs，and metabolic disorders are the important reasons for the infrared characteristics of MS.