Schizophrenia is a severe mental illness, characterized for strong disorganization of the mental process, manifested through of a variety of symptoms. It is considered like one of the most serious psychiatry illness and became, with the increase of many researches accumulated in the last two decade, recognized as a cerebral disease, although hereditary and environmental factors also seems to contribute to its development. The objective of this study was to verify if psychological investigations methods could disclose patterns which could help in the schizophrenia diagnoses, contributing to the understanding of the mental arrangement in this process. Across a comparative study of two monozigotic twin brothers, using the Desiderative Questionnaire and Human Figure Draw analysing based in the Deterioration Escore of the Human Figure Draw (Freitas Junior, 1968), it was possible to detect common psychopathological indicators of the schizophrenia process. Therefore, this study achieved the proposal objective, possibiliting the utilization of these psychological techniques in the psychiatry courses.