Global warming induces a dramatic elevation of heat-related morbidity and mortality worldwide. Individual variation of heat stress vulnerability depends on various factors such as age, gender, living area and conditions, health status, and individual innate characteristics. Sasang typology is a unique form of Korean traditional medicine, which is based on the hypothesis that constitution-specific traits of an individual determine the particular distinctive tendency in various aspects, including responses to the external environment. Recent scientific evidence shows that Sasang types differ in body composition, metabolic profile, susceptibility to certain disease patterns, and perspiration. This review aims to interpret these findings under the context of heat balance consisting of heat production (Hprod), heat loss (Hloss), and heat load (Hload). Based on the published data, at a given body mass, the TaeEum type tended to have a lower Hprod at rest and at the exhaustion state, which may indicate the lower metabolic efficiency of this type. Meanwhile, the surface-to-mass ratio and heat capacity of the TaeEum type appear to be lower, implying a lower heat dissipation capacity and heat storage tolerance. Thus, because of these characteristics, the TaeEum type seems to be more vulnerable to heat stress than the other constitutions. Differences in temperature regulation across constitutional types should be taken into account in daily physical activity, health management, and medical research.