This paper discusses the important significance of theory of liver-wood characterized by bending and straightening in the doctrine of liver viscera picture of traditional Chinese medicine and the clinical hepatopathy. It is considered that this theory should be interpreted as the physiological characteristics and function of liver,including liver being bold and firm viscera as well as soft and mild viscera,liver being substantial yin and functional yang,liver controlling conveyance and dispersion,liver storing blood,liver governing ascending and dredging. In the clinical complicated liver diseases,based on the full understanding of physiological characteristics and function of liver,the conventional therapy such as nourishing and regulating liver,and the flexibly modified therapy which combined with the disease condition,seasons and other organs,can be used in the treatment.