Arthrobotrys oligospora is a carnivorous fungus that can use mycelia trapping devices to capture their prey. Three novel oligosporons, named arthrobotrisins A-C (1-3), were isolated from A. oligospora and identified by spectroscopic analysis in combination with X-ray diffraction. This is the first time that the relative configuration of naturally occurring oligosporon metabolites has been fully determined. Compound 3 exhibited specific antibacterial activities.