To study the chemical constituents from the aerial part of Hypericum scabrum, ten polyprenylated acylphloroglucinol derivatives were isolated from the ethanol extract of H. scabrum,including a new compound hyperibrin H (1).The other compounds were elucidated as:hypermongone A (2),hypermongone E (3),hypermongone F (4),hypermongone G (5),hypermongone H (6),sampsonione L (7),garcinielliptone I (8),propolone C (9),and garcinielliptone N (10).Compounds 2-10 were isolated from this plant for the first time.Compounds 5 and 6 showed neuroprotective activity against glutamate-induced toxicity in SK-N-SH cells at 10 μM.