Limonoids from the seeds of Xylocarpus moluccensis,collected in the mangrove swamp of Krishna estuary,Andhra Pradesh in India,were investigated. Eleven compounds were isolated and purified by extraction with 95% ethanol,and ethyl acetate,silica gel,ODS gel column chromatography,and high performance liquid chromatography (HPLC). The structures were confirmed by NMR spectra,and ESI-MS. All compounds were isolated for the first time from X. moluccensis,and compound 1 was identified as a new mexicanolide limonoid,named krishnolide E. Furthermore,compound 1 exhibited inhibitory effect on human carboxylesterase 2(CES2) with inhibition rate of 63% at the concentration of 100.0 μM.