ObjectiveTo investigate the causes of an outbreak of measles in a pediatric ward of a hospital , and provide scientific measures for the control of healthcareassociated infection.MethodsMedical data of 4 cases of measles in a pediatric ward from December 6-30，2008 were analyzed retrospectively.ResultsMeasles virus antibody IgM in 4 children were all positive, one child initially developed measles , all the other 3 children had history of contacting with the first case, the duration of measles was shorter than the average latent period of measles (about 2 weeks).ConclusionMeasles virus is the cause of this outbreak, infection outbreak can be reduced by establishing the early warning mechanism, adopting strict isolation measures, strengthening hand hygiene of healthcare workers, emphasizing disinfection of surface and environment ,and reducing patient care attendants and visitors.