During an epizootic outbreak of yellow fever ocurred in the year of 1973 in the north and middte west regions of Brazil, histopatological slides of liver material were made from suspected cases removed by viscerotomy and necropsies. There where diagnosed 57 positive cases. The histopatological slides demonstrated that there are no differences between the cases of the disease in Africa and South America. The histopatological diagnosis goes on based on the Hver, in the Councilman lesion, in hyperplasia and hypertrophy of the Kupfer cells, in delayed cases. There was no histological difference between the cases described in urban yellow fever epidemics and epidemic andenzootic outbreaks of jungle yellow fever in the last 43 years.