Review of Literature on Languor and fatigue. According to comparative studies of Oriental and Western medical Literature on the Languor and fatigue on causes and symptom, flowing results were obtained. 1. Common etiologies of the Languor and fatigue in Western medicine are firstly exhaustion of energy, secondly variation of control center-neurotic and body fluid control-, thirdly variation of a living body physico chemical state, forthly production of middle metabolic product, fifthly psychological instability. 2. The expression of the Languor and fatigue in Oriental medicine are consumption, dificiency of vital energy(氣虛), illness caused by overexertion and dificiency of essence of life(精虛). The caure of the Languor and fatigue are dificiency in spleen and stomach(脾胃虛弱), dificiency of both the lung and kidney(肺腎兩虛), the six excessive(六淫), irregular life and excessive mental labor. 3. The symptomes of the Languor and fatigue in western medicine are systemic feeling of fatigue, dislike of work, Dizziness, general fatigue, anorexia, painful body, nerveous prostration. anxiety and decrese of energy, and in oriental medicine dificiency of vital energy, general pain, sinking of vital energy(氣虛下階) in adequate nutrition, confusion and slow speaking.