Bioassay-guided fractionation of roots and stems of Ardisia virens Kurz (Myrsinaceae) led to isolation of fourteen compounds, (2'R)-6-(2'-acetoxypentadecyl)-5-hydroxy-2-methoxy-1,4-benzoquinone (1), (2'R)-6-(2'-acetoxytridecyl)-5-hydroxy-2-methoxy-1,4-benzoquinone (2), (2'R)-6-(2'-acetoxytridecyl)-2-methoxy-1,4-dihydroxybenzene (3), (2'R)-6-(2'-acetoxytridecyl)-5-formyl-2-methoxy-1,4-dihydroxybenzene (4), 1-(3,5-dihydroxyphenyl)nonan-1-one (5), 1-(3-hydroxy-5-methoxyphenyl)pentan-1-one (6), (2'S)-3-hydroxy-5-methoxyphenyl-2'-tridecanol (7), (2'S)-3-hydroxy-5-methoxyphenyl-2'-pentadecanol (8), (2'S)-5-acetoxy-3-hydroxyphenyl-2'-tetradecanol (9), 1-acetoxy-2-methoxy-6-pentadecyl-4-hydroxybenzene (10), 1-acetoxy-2-methoxy-6-tridecyl-4-hydroxybenzene (11), (2'R)-1-acetoxy-6-(2'-acetoxy-tridecyl)-2-methoxy-4-hydroxybenzene (12), (2'R)-1-acetoxy-6-(2'-acetoxypentadecyl)-2-methoxy-4-hydroxybenzene (13), and 1-acetoxy-6-(2'-ketopentadecyl)-2-methoxy-4-hydroxylbenzene (14), together with thirty-four other known compounds, of which three, 1-(3,5-dihydroxyphenyl)pentan-1-one (15), 1-(3,5-dihydroxyphenyl)heptan-1-one (16), and 1-(3,5-dihydroxyphenyl)pentadecan-1-one (17), were isolated for the first time from a natural source. Their structures were elucidated by analyses of spectroscopic data. Seven cytotoxic constituents were found to be 3, 10-12, ardisianone (18), cornudentanone (19), and ardisianol (31) with cytotoxic properties (IC(50) values < or =4 microg/mL) against MCF-7, NCI-H460 and SF-268 cancer cell lines in vitro.