A new anthraquinone compound, 1,3-dihydroxy-6-methoxy-2-methoxymethyl-9,10-anthraquinone (1), along with four known analogues (2-5) were isolated from the roots of Prismatomeris tetrandra. Their structures were elucidated on the basis of spectroscopic analysis. Among these compounds, lucidin omega-methyl ether (4) and lucidin omega-ethyl ether (5) were isolated from this genus for the first time. Compound 1 showed weak cytotoxic activity against A549 and LAC cell lines.