We investigated the effects of Fomitopsis pinicola extract on biological activity by examining the antioxidant and antitumor activity in vitro and in vivo. When the F. pinicola extract concentration was raised from 60 to $120{mu}g/mL$, the DPPH scavenging rate increased from 50.3 to 88.2% and the superoxide anion radical scavenging rate increased from 45.2 to 85.3% when the F. pinicola extract concentration was raised from 500 to $700{mu}g/mL$. After incubating F. pinicola extract for 12 h, the linoleic acid scavenging rate increased from 35.5 to 90.5%. A similar finding was observed for butylated hydroxytoluene. The total phenolic content of the F. pinicola extracts were approximately 10- to 16-fold higher than what was observed in the P. nebrodensis and A. camphorate extracts. The glutathione production, using decoctions prepared from F. pinicola, was $20.0{mu}M/g$ of liver, which corresponded to approximately 4.0-fold higher than the control. The glutathione peroxidase activity was 8.3 U/mg of protein, which was approximately 2.8-fold higher than the activity level observed in the control rat livers. The cell viability rates of all the human cancer cells, when $100{mu}g/mL$ of ethanol extract was used for the different types of cancer cells, decreased with increasing extract concentrations in comparison to the hot water extract. In particular, when HeLa and Hep3B cells were incubated with $1000{mu}g/mL$ of methanol extract, the cell viability rates were 20 and 25%, respectively, which was approximately 3.0-fold higher than what was observed for the hot water extract.