To increase antioxidative activity and minimize off-flavor of Chungkukjang, Seoliate as main ingredient and green tea as minor ingredient were selected. The protective efffect of green tea for Chungkukjang was evaluated under in vitro. Seolitae Chungkukjang added with green tea (SCG) was prepared on the basis of the protective effect of green tea from oxidative stress. Green tea showed the strong protective effect against nitric oxide (NO) and superoxide anion ($O_2{^-}$) radicals. The SCG perparation method was as follows. Seolitae was cleaned and washed, soaked in 1.5-fold water ($15^{circ}C$) of Seolitae weight for 48 hr. Seolitae was steamed about 40 min by autoclave and then cooled about $40^{circ}C$. Bacillus subtilis was inoculated and 5.0-fold green tea of weight was added, and then it was fermented for 60 hr at $40^{circ}C$. According to the preparation method, Seolitae Chungkukjang (SC) and Seolitae Chungkukjang added with green tea 5.0% (SCG5.0) were prepared. Among the Chungkukjang groups SCG5.0 exerted more effective scavenging activity of NO than SC. In addition, SC added with green tea 5.0% showed high $O_2{^-}$ scavenging effect. These results suggest the antioxidative potential against free radical-induced oxidative damage of SCG.