The use of the emergency room of a hospital during a year has been studied, in the last few years, the use of hospital emergency rooms has increased alarmingly, and a large number of patients come by their own initiative. With regard to this problem, we have considered it adequate to carry out this survey, in order to know the situation of hospital emergency rooms in our community.We carry out a retrospective study from an aleatory representative sample of patients, cared during a year (from June, 1987 to June 1988) in the hospital emergency room of a health area in Asturias.Frequentation was 116 per a thousand inhabitants a year and old-aged population constituted the largest number of people using this unit. The largest inflow of patients took place at 12 to 14 hours. Men came with a significant higher frequency than women. More than a half of patients came upon their own initiative. The percentage of justified admissions and emergencies was significatively higher among the patients sent by a doctor than among those ones who came by their own initiative, an it was higher when the doctor belonged to a Health Care Center, compared with doctors belonging to the traditional model.There exists a high index of non-justified emergencies and the hospital is used as a Primary Health Care center.