From the stems of Mahonia nepalensis, five compounds were isolated: 1-C-syringylglycerol 4-O--Dglucopyranoside(1), 5,6-dihydro-2,3,9,12-tetramethoxydibenzo quinolizinium (2), 7-hydroxy-6-methoxyisochroman-1-one (3) and 6,7-dimethoxyisochroman-1-one (4), 4’,7-dihydroxyflavanone (5).The chemical structure of these compounds were elucidated by their NMR spectra and comparison withreferences.Keywords: Mahonia nepalensis, isochroman-1-one, flavanone, dibenzoquinolizinium