The number of persons over 65 years of age with schizophrenia will increase in the future. Geriatric schizophrenia involves bizarre delusions and hallucinations similar to those occurring in younger schizophrenic patients. Delusions of an elderly delusional disorder patient focusing on the family and environment easily lead to social withdrawal. Persons becoming ill with initial psychosis at an older age should be subjected to thorough diagnostic examinations. Organic brain diseases constitute the major differential diagnostic illnesses. Second generation antipsychotics are the first-line drugs in the treatment of geriatric schizophrenia and delusional disorder. The patients benefit from a regular therapeutic contact and treatment of associated diseases.