Self-harm is described as a wide range of things that people do to themselves in a deliberate and usually hidden way, which are damaging. Some forms of self-harm carry a serious risk, but this does not mean that someone's self-harm is always intending to cause themselves serious injury or death. Psychoanalysis is mainly interested in exploration of the unconscious mind. Usually, the interpretation of the biographic (personal) events during the psychoanalytical cure is able to settle the frame of the individual's psychopathology. The use of the play technique had opened a new field of investigation of the unconscious. The observation of children's play express their fantasies and anxieties. Research shows that children's play could be situated within the framework of the ego's attempts to defend itself from instinctual conflicts in order to work them out. This leads to the conception of symbolism, a psychic mechanism that is essential for development of the ego. As an example of the above theses a description of dynamics inner world dynamics of seventeen years old girl who undertook acts of self-mutilation are quoted.