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Atta cephalotes (Hymenoptera: Myrmicinae) is a dominant species of leafcutter ant in some Latin American countries, and its high abundance and varied defence mechanisms have made it an agricultural and urban pest that is difficult to control. The use of chemical control has an adverse impact on the environment and human health; for that reason, microbiological control is a viable and desirable alternative. From this perspective, we assessed the entomopathogenic capacity of nine fungi isolated from the waste produced by laboratory colonies. For each treatment, 210 workers were distributed in fourteen 15-ant experimental units, each individual being washed in a 108 conidia/mL suspension for ten seconds. A negative control consisting of sterile peptone and two positive controls, commercial strains of Beauveria bassiana and Metarhizium anisopliaesensu lato, were established. In total, 12 treatments were assessed and the response variable was the corrected cumulative mortality over ten days. Data from the five fungi isolates demonstrated entomopathogenic capacity. On the sixth day after exposure, a strain of Aspergillus flavus produced the highest mortality rate (91.5%) while Penicillium commune (85.3%), Aspergillus ochraceus (79.2%) and Fusarium proliferatum (61.7%) showed lower mortality rates. Both native A. flavus and P. commune fungal isolates resulted in higher mortality than the two commercial strains, showing them to be promising control agents for A. cephalotes workers. [ABSTRACT FROM AUTHOR]