Depression has become a common disease，and more and more people are suffering both mental and physical torture. It is common to treat the disease with traditional Chinese medicine by regulating liver because it is well accepted that the core pathogenesis of depression is the stagnation of liver qi.But I think that the deficiency of kidney-yang is another significant pathogenesis of depression according to its clinical manifestation and the traditional Chinese medicine theory. This paper discusses the relationship between the deficiency of kidney-yang and depression based on the psychosomatic theory of traditional Chinese medicine and states the importance of kidney-yang to the treatment of depression disorder. This article also emphasizes that warming and invigorating kidney-yang would take an important role in treating depression. I hope the viewpoint of the paper may exploit the new thought of treating depression in order to relieve physical and mental suffering for patients.