As distinct from the Western medical concept of Kidneys, this concept from Traditional Chinese Medicine is more a way of describing a set of interrelated parts than an anatomical organ. (See Zang Fu theory)

To differentiate between western or eastern concepts of organs the first letter is capitalized (Liver, instead of liver, Spleen instead of spleen). Because Traditional Chinese Medicine (TCM) is wholistic, each organ cannot be explained fully unless the TCM relationship/homeostasis with the other organs is understood. TCM also looks at the functions of the organs rather than fixed areas and, therefore, describes different organs that are not actually physical, like the Triple Burner (San Jiao). This also leads to controversy about the validity of TCM, which comes a lot from the difficulty of translating and lack knowledge about TCM concepts and Chinese culture. So, to avoid conflict and to keep an open mind, please realize that these notions evolved in a different culture and are a different way of viewing the human body.

The Kidneys (Shen) is a Zang organ meaning it is a Yin organ. The other Yin, or Zang, Organs are the Lungs (Fei), Liver (Gan), Spleen (Pi), and Heart (Xin). Sometimes the Pericardium (Xin Bao) is included. Yin organs store, secrete, make, and transform Essence, Blood, Spirit, Qi, and Fluids. These nourish the body.

The Kidneys store the Essence (Jing) and are considered the root of everything. The Kidneys govern water metabolism, reproduction, secretions and some brain functions. The Kidneys are responsible for growth and development. The Kidneys produce Marrow, dominate Bones, and manufacture Blood. The Kidneys open into the ears. They receive Qi from the air (Kong Qi). Open at the two yins, (anus and genitals). Health of the Kidneys is reflected in head hair. Houses the Zhi (or will). Fluid secretions are urine, semen, and vaginal fluids. The peak time for the Kidneys is from 5-7pm.