This study was performed to investigate the effects of fermented extract of Pinus densiflora (FPD) on oxygen radicals and $H_2O_2$-induced damage. The results are as follows: 1. The 1.1-diphenyl-2-picrylhydrazyl (DPPH) free radicals were considerably reduced by FPD and $IC_{50}$ value was showed the concentration of 20 ㎍／㎖. 2. The cytotoxicity did not observe by FPD treatment in A548 cells. 3. The $H_2O_2$-induced cell damage was recovered by FPD pretreatment in A549 cells. These results suggest that FPD, as a natural antioxidant, has scavenging effect of free radicals and protection effect from $H_2O_2$-induced cytotoxicity.