With the improvement of modern living standards,the formation of unhealthy dietary habits,such as excessive consumption of rich and greasy foods,overeating,and consuming cold foods,has led to impaired spleen function and the endogenous generation of phlegm and dampness in an increasing number of people."Many diseases are caused by phlegm",as numerous clinical conditions are often induced by or accompanied by the formation of phlegm and dampness.Wendan Decoction is a commonly used formula in the clinical treatment of phlegm.It can be modified and applied for patients with phlegm-dampness and internal heat.This paper primarily explores the clinical applications of Wendan Decoction in treating common diseases such as insomnia,stomach pain,dizziness,coronary heart disease,neurosis,and chronic pharyngitis,aiming to provide a reference for the clinical treatment of phlegm-dampness conditions.