The essential oil of Aniba hostmanniana (Nees) Mez, family Lauraceae, was obtained from fresh leaves by hydrodistillation. The chemical composition of the oil was assessed using gas chromatography with mass spectrometric detection (GC-MS). The antimicrobial activity of the essential oil was tested against Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumonia) and the Gram-positive bacterium Staphylococcus aureus. GC-MS analysis revealed the presence of 35 compounds in the essential oil, the predominant ones being benzyl benzoate (29.3%), δ-cadinene (12%), β-caryophyllene (10.5%), bicyclogermacrene (5.9%), and α-copaene (3.9%). The oil showed activity against most of the bacterial strains studied.