According　to　the　pathogenesis　of　Alzheimer＇s　disease　(AD),　beta-amyloid　protein　(A　beta)　was　directly　toxic　to　neurons,　leading　to　neurodegeneration.　Total　saponin　of　Dipsacus　asperoides　(tSDA)　is　one　of　the　main　ingredients　of　Dipsacus　asperoide,　a　traditional　Chinese　medicine.　To　explore　the　effects　of　tSDA　on　neuronal　damage　induced　by　A　beta　in　vitro,　biochemical　analysis　combining　primary　cultured　neurons　were　adopted.　Neurons　were　treated　with　35　mmol/L　A　beta　for　24　h,　and　tSDA　at　concentrations　of　1-300　mg/L　were　added　to　A　beta-treated　cultures　24　h　in　advance,　A　beta　for　24　h,　the　survival　rate　of　neurons　decreased　closely　by　50%.　Lactate　dehydrogenase　release　and　the　Malondialdehyde　(MDA)　level　increased　substantially.　However,　if　neurons　were　pretreated　with　tSDA,　the　survival　rate　of　neurons　was　higher　than　A　beta-treated　alone.　Lactate　dehydrogenase　release　and　the　MDA　level　decreased　distinctly.　Results　demonstrated　that　tSDA　possessed　a　neuroprotective　action　and　that　tSDA　protected　neurons　against　the　toxicity　of　A　beta,　most　likely　by　relieving　oxidative　stress　or　inhibiting　the　process　of　A　beta,　inducing　free　radical　generation.