This paper deals with the theme of truth and illusion in Tender is the night. The novel tells the story of American Psychologist Dick Diver and his wife, the wealthy but psychologically unstable Nicole. The novel relates the disintegration and collapse of its hero Dick Diver on the moral, psychological and social levels. Dick begins his life with a moral advise from his father that “nothing could be superior to good instincts, honour, courtesy and courage”. But the pressure of a materialistic age nullify his beliefs in the essential goodness of man.