Clinical features of messianic delusions in endogenous psychoses have been retrospectively studied in 75 patients (33 male, 42 female, aged 16-62 years, illness duration from 0.5 to 39 years) with diagnosis paranoid schizophrenia, continuous type (F20.00)--18 patients, attack like progressive type (F20.02)--17 patients, schizoaffective disorder (F25)--27 and acute polymorphic psychotic disorder (F23.03)--13. Being a kind of delusion of grandeur, messianic delusion is characterized by destruction of "self" as break with the past experience, transformation to mythological characters (total depersonalization) and assignment of supernatural power. Its content is similar to apocalyptical, mystical, antagonistic (Manicheam) delusions. Formation of the delusion plot occurred in the framework of hallucinate-paranoid syndrome received its greatest expression in the structure of paraphrenic and oneiroid syndromes. The volume of its content, duration and mechanisms of delusion formation (hallucinative, sensual and delusion of imagination) were defined by a form of schizophrenic psychosis. Sometimes such patients confer social danger and demand more attention from psychiatrists.