The pyrrolizidine alkaloids(PAs) in leaf of Gynura divaricata(L.) DC.was analyzed by LC-MSn technique.The result shows that two hepatotoxic pyrrolizidine alkaloids(HPAs) are detected from the methanol extract of G.divaricata leaf,with relative molecular weight of 335 and 365,respectively and lower content.The constituent with relative molecular weight 335 is a retronecine-type alkaloid,and identified as integerrimine;another constituent with relative molecular weight 365 is an otonecine-type alkaloid,speculated to be isomer of usaramine or 18-hydroxyinterrimine.