Enterobactérias foram identificadas em adultos de Musca domestica (Linnaeus, 1758) (Diptera: Muscidae) e Chrysomya megacephala (Fabricius, 1754) (Diptera: Calliphoridae). Ambas as espécies foram capturadas no Jardim Zoológico da cidade do Rio de Janeiro e tiveram a superfície externa do corpo lavada e o sistema digestivo dissecado, para análise bacteriológica. Identificaram-se Escherichia coli, Citrobacter sp., Proteus mirabilis, Morganella sp., Klebsiella sp., Pseudomonas sp., Enterobacter sp. e Salmonella Agona. P. mirabilis foi o isolado bacteriano mais freqüente. Em duas amostragens (8%) de C. megacephala, isolou-se Salmonella Agona. As amostras de E. coli não foram enteropatogênicas. M. domestica e C. megacephala são potenciais veiculadoras de bactérias causadoras de enterites em humanos e animais.Enterobacteria were identified in adults of Musca domestica (Linnaeus, 1758) (Diptera: Muscidae) and Chrysomya megacephala (Fabricius, 1754) (Diptera: Calliphoridae). Both species were captured in the Zoo of Rio de Janeiro. They had their external body surface washed and their digestive system dissected for bacteriological analysis. Escherichia coli, Citrobacter sp., Proteus mirabilis, Morganella sp., Klebsiella sp., Pseudomonas sp., Enterobacter sp. and Salmonella serovar Agona were isolated in the samples. P. mirabilis was the species most frequent isolated. Strains of Salmonella Agona were isolated from two samples (8%) of C. megacephala. Enteropathogenic E. coli was not isolated. M. domestica and C. megacephala showed themselves as potential vectors of agents related to enteric diseases in humans and other animals.