Seven alkaloids were isolated from the seeds of Ammopiptanthus mongolica by thin layer chromatography and silica gel column chromatography, and the chemical structures of five alkaloids, 17-oxosparteine, ?-isosparteine, 3?-hydroxysparteine, sparteine, and 3?-hydroxysparteine were identified by 1H nuclear magnetic resonance (NMR) and electron ionization mass spectrum (EIMS).