Wild grass is edible, and it grows in the mountains or field areas. Wild grass has diverse biological effects, such as antiobesity, anti-cancer, antioxidant activities and immune stimulation. Currently, many studies are aimed at enhancing the efficacy of medicinal foods on biological activity using a bioconversion technology, including the fermentation process. In this study, the quality characteristics and antioxidative activity of the fermented wild grass was investigated. The antioxidant activity of fermented wild grass was assessed by various radical scavenging assays using DPPH(2, 2-diphenyl-1-picrylhydrazyl), FRAP(ferric ion reducing antioxidant power), reducing power, and ABTS (2, 2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)). Moisture contents of the fermented wild grass is 49.6±0.06%. Contents of crude ash, crude protein, and crude fat were 0.65±0.01, 0.65±0.04, and 3.3±0.59%, respectively. Moreover, fermented wild grass showed that the hunter's color values were 80.36(lightnees), 11.47(redness), and 44.53(yellowness), respectively. Total phenolic contents of the fermented wild grass was 1, 185±159 ㎍ GAE(gallic acid equivalent)/g. The antioxidative activities of the fermented wild grass were significantly increased in a dose dependent manner. In addition, fermented wild grass did not show any cytotoxicity up to 500 ㎍/㎖. However, the anti-adipogenic effect of the fermented wild grass extract was barely detectable. This antioxidant potential is partly due to the phenolic compounds that are present in the fermented wild grass extracts.