Twenty-six known compounds and two new compounds, including a new lignan, (7S*,8R*,7'R*,8'S*)-icariol A₂-9-O-β-xylopyranoside (1), and a new indole alkaloid, hygarine (2), were isolated from the extracts of Hygroryza aristata (Gramineae). The structures of all compounds were elucidated on the basis of NMR spectral analysis. The compounds (-)-epigallocatechin-3-O-gallate (4) and (-)-epicatechin-3-O-gallate (5) possess free radical scavenging activities and compound 1 could inhibit superoxide anion generation and elastase release by fMLP/CB-induced human neutrophils with IC₅₀ values of 19.33 ± 0.86 and 24.14 ± 1.59 μM, respectively.