Based on the comprehensive combing of the connotation and application of “heat retention”, it is believed that heat retention is a pathological change of heat evil and tangible things such as phlegm fluid and blood stasis. Among them, heat evil and tangible are the necessary conditions for heat retention. Both are indispensable. Heat retention often occurs in hollow organs, and can also be found in skin, fascia, tendons and other parts of the acne, common diseases such as rickets, skin diseases, gynecological diseases. The treatment of heat retention is mainly based on clearing heat and dispersing. According to the difference of tangible things such as food, dead blood and phlegm, it is treated with clearing the hollow viscera and venting heat, cooling blood and promoting blood circulation, clearing away heat and removing phlegm, clearing away heat and detoxifying.