RESUMEN
The thoroughfare vessel is one of eight extra meridians and named sea of viscera, sea of blood and sea of twelve meridians. The thoroughfare vessel is closely related to qi and blood and has important guiding significance for clinical practice. Analysis of literature about the thoroughfare vessel finds that the literature of past dynasties has different descriptions of the initial site of the thoroughfare vessel. Qichong, infrarenal, Guanyuan and uterus were considered as its initial site. By summarizing the related statements of past dynasties, this article analyzes different initial sites of the thoroughfare vessel and considers that infrarenal uterus is the initial site of the thoroughfare vessel. That not only enriches and develops the physiological and pathological theories of the thoroughfare vessel and endows the thoroughfare vessel with more extensive contents but also provides more clinical guidance.