The aim of the study was to analyze a demographic situation in St. Petersburg with a special attention to the oldest old. The proportion of long-living persons in total population is increasing in all developed countries. The rate of elderly people grows rapidly alongside with the decrease of the birth rate. The number of the oldest people (90+) has grown especially rapidly during the last decade--from 5.9 to 11 thousands in St. Petersburg. Frequency of visits to general practitional, specialist, and emergency for medical aid during 1996-2002 have been studied in the city. Special groups of centenarians have been selected. 396 persons over 85+ years were under observation in the basic group. There were 38 centenarians among them. Seventy-one person of 40-55 year-old and 110 persons of 65-75 year-old were included in the control group. Elderly people have specific medical problems: vascular or Alzheimer-type dementia, osteoporoses and its complications, diabetes, incontinence, diseases of sense organs. The incidence of an appeal to the urgent medical aid was higher among persons of control group than that in the 85+ group. There were more cases of chronic pathology and less cases of acute diseases in the oldest group as compared with young ones. In centenarians, address for different kinds of a medical care is reduced in comparison with other age groups of long-livers. There were no registered oncological pathologies and "disappearing" of some chronic diseases have been observed in centenarians. CONCLUSIONS Our study prove the necessity of the creation of medical and social geriatric services in the city. The improve of the qualifications of geriatricians is an important task.