Asparagus oligoclonos is one of the endemic halophytes used folk medicine in Korea. We isolated the main compound rutin from methanol extracts of A. oligoclonos based on nuclear magnetic resonance and TOF ESI-MS data. We have investigated the quantitative analysis method of main compound using HPLC and the results exhibit that rutin content of A.oligoclonos were 1.816%. To explore anti-oxidant from A. oligoclonos ethanol extracts (AOE), we investigated the antioxidant effects of AOE on H₂O₂-induced oxidative stress in RAW 264.7 cell. AOE were reduced H₂O₂-induced oxidative stress via enhancement of cell viability, and AOE significantly decreased ROS production depending on concentration. Next, to screen for anti-inflammatory activity of AOE, we investigated the inhibitory effects of AOE in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. AOE had no effect on cell viability at a concentration of 500 μg/mL. Nitric oxide (NO) production inhibited in a dose-dependent manner. These results suggest that AOE may be a useful antioxidant and anti-inflammatory agent.