A new 5-acyl-2-methylpyrrole, isolated from the endophytic fungus S20 of Cephalotaxus hainanensis, was elucidated as 1-(5-methyl-1H-pyrrol-2-yl)-2-((2S*,3R*)-3-((E)-prop-1-enyl)oxiran-2-yl)ethanone (1) on the basis of spectroscopic evidence, including 1D- and 2D-NMR (HMQC, 1H-1H COSY, HMBC and ROESY) and MS analysis. Compound 1 showed inhibitory effects on Staphylococcus aureus and methicillin-resistant S. aureus by the filter paper disc agar diffusion method.