This article approaches certain aspects of fantasmatic of Theresa of Lisieux at the time of her preadolescence and its puberty. It reveals psychic conflicts marked by death and violence, as well as by the strength of the oedipian affects and by an impossible sexuality. It tries to show that if the psychical reality of « little Theresa » is far from corresponding to the sweetened image that we are usually made, it reveals not less the quality of the work of the life instincts and the strength of a remarkable process of maturation which known how to transform gradually a pathological and mortiferous psychic organization into a dynamics turned to the life.