OBJECTIVE: To describe the occurrence of transient pancytopenia induced by parvovirus B19 infection in a patient with hereditary hemolytic anemia and to discuss the importance of the diagnosis of this pathology.METHODS: Case report of a child whose diagnosis was made by polymerase chain reaction (PCR) and serology, and review of the literature.CLINICAL REPORT: A twelve year-old male patient with hereditary spherocytosis, presenting non-specific symptoms of an infectious syndrome followed by severe and transient pancytopenia, whose diagnosis was a parvovirus B19 infection.CONCLUSION: The diagnosis of parvovirus infection has a particular importance in hematology, especially on some morbid conditions, among them the hereditary hemolytic anemias. PCR is useful because of its rapidness and sensitivity on the specific diagnosis of this disease.