Two new indole alkaloids, 1-(5-prenyl-1H-indol-3-yl)propan-2-one (1) and 1-(6-methoxy-5-prenyl-1H-indol-3-yl)propan-2-one (2), along with five known ones (3–7) were isolated from the fermentation products of a cigar tobacco-derived endophytic fungus Aspergillus fumigatus. Their structures were elucidated by spectroscopic methods, including extensive 1D and 2D NMR techniques. Compounds 1 and 2 were evaluated for their anti-tobacco mosaic virus (anti-TMV). The results showed that compounds 1 and 2 exhibited potential anti-TMV activities with inhibition rates of 26.5 and 28.8%, respectively. © 2023, Springer Science+Business Media, LLC, part of Springer Nature.