The traits of age thinking development (formation) were studied by experimental and psychological tests in children aged from 5 to 14 years who were diagnosed as suffering from favorably developing forms of schizophrenia. During all the age periods this group of children showed a deviation in the thinking development, compared to that of the control normal group. The tests detected an abnormal form of thinking not described before which was characterized by typical changes in the interrelationship and dynamics of 2 significant sides of thinking activity. The dysharmony and asynchronism of development were expressed in a drop of the rate and in a specific pattern of forming selectivity of knowledge actualization. On the other hand, it was demonstrated that there was an accelerated development of formal and logical aspects, operational side of thinking. The results obtained allow a new approach to some traits of intellectual activity inschizophrenia and indicate their relation with some personality traits.