A total of 46 psychopathic personalities from 30 to 55 years of age were studied. Of them 40 subjects were examined by follow-up checkings. Under psychotraumatizing situations these patients demonstrated acute paranoiac syndromes the content of which was characterized by monotopical delusional ideas. The formation of such acute paranoiac reactions was determined by abnormal personality structures and by individual pathogenic psychotraumatizing situations. The paper contains a description of the psycho-pathological traits of acute paranoiac states in psychopaths and their impact on the general development of psychopathy.