Psidium striatulum is a fruit popularly known as araçá or araçari in region from Brazilian Amazon. These fruits are widely used in folk medicine for the treatment of diarrhea and infections caused by microorganisms that cause harm to human health. Thus, this work aims to characterize the chemical profile and biological evaluation of the essential oil of the green fruits of Psidium striatulum DC. The plant material was collected in the municipality of Boa Vista-RR, on the margin of Rio Branco and submitted to hydrodestillation, in a Clevenger, Spell brand double - condenser type device for 2 hour interrupt period. Identification and quantification of twenty volatile constituents corresponding to 91.9% of its composition was provided through GC-MS and GC-FID, with 8.1% remaining unidentified, with the majority of a-pinene (11.9%), humulene (10.4%), a-copaene (7.1%), globulol (5.7%), d-cadinene (4.2%) and ß-pinene (4.2%). Microbiological tests of essential oil at 250 µg/mL were performed against Staphylococcus aureus, ATCC 29212 (67.03±4.06%); Bacillus cereus, ATCC 11778 (73.14±2.70%); Escherichia coli, ATCC 25922 (11.47±0.28%); Salmonella typhimurium, ATCC 14028 (78.43±2.12%) and C. albicans (13.18±1.69%) and showed moderate inhibitory activity for the AChE enzyme (44.42%). The results showed that the essential oil had an activity greater than 65% against Staphylococcus aureus, Bacillus cereus and Salmonella typhimurium, as well as having a moderate inhibitory effect on the enzyme acetylcholinesterase (AChE) in the conduction conditions of the bioassays of the present study.