ABSTRACT-Plants of Polygalaceae family are source of several compounds such as xanthones, coumarins, phenols, triterpenes, steroids, pyrones derivatives and alkaloids. These plants contain chemical compounds with a large spectrum of biological activities, including anti-depressant and anti-angiogenic. Moutabea guianensis is an Amazonian species belongs to the Polygalaceae family. In this work, from roots of M. guianensis were isolated a new xanthone, 3,8-dihydroxy-1,2,4,5-tetramethoxyxanthone, named moutabeone D, and one known xanthone, 1,3,5-trihydroxy-2-methoxyxanthone. Column chromatography on silica gel and semi-preparative HPLC led the isolation of these compounds. The structures were elucidated by spectroscopic data (HRESIMS, UV, IR, 1D and 2D NMR).