Authors present the results of the evaluation of some epidemiological and clinical parameters, on a sample of 2101 inpatients suffering from mumps, hospitalized in the Clinic of Infectious Diseases Iaşi, between 1981-2003. The annual hospitalization average was of 5.7%. Authors highlight a high incidence of mumps in males (68.1%), urban area (67.8%), and winter-spring season (62%). The most affected was the age group of 7-10 (21.5%), followed by 11-14 (17.3%), and 1-6 (16.7%) and inpatients over 20 years old registered 25.1%. The clinical forms were varied: 30.6% cases without the affection of other glands and organs; 26.1% associated meningitis; 15.6% with orchitis; 2.5% with pancreatitis. Meningitis and orchitis were pointed out as primary infection in 3.8% and 3.4% cases, respectively. The clinical manifestation forms were: mild (14.8%); medium (84.5%), and severe (0.5%) and 146 cases (6.9%) were registered as nosocomial infection. The nature of the epidemic foci was established retrospectively: school (5.9%), preschool (1.4%), and familial (92.7%). All these aspects highlight the necessity of the epidemiological surveillance of risk groups and the inclusion of anti-mumps vaccine-prevention in the Extended Immunization Program.