Objective : The objective of this study was to compare the antioxidant effects of hot pepper extract and capsaicin. Methods : In vitro, antioxidant activities were examined by DPPH radical scavenging activity, total antioxidant capacity(TAC), oxygen radical scavenging capacity(ORAC), inhibition of induced lipid peroxidation using liver mitochonria and total phenolic contents. Results : 1. DPPH free radical scavenging activities at the concentrations of both 1 and $10mg/m{ell}$ were 1.2 to 1.9 times higher in capsaicin than in hot pepper extract. The concentration of capsaicin required for 50% radical scavenging was lower than that of hot pepper extract(3.9 vs $5.9mg/m{ell}$), indicating that capsaicin had higher DPPH radical scavenging activity than hot pepper extract. 2. Total antioxidant capacities of capsaicin at the concentrations of 0.1 and 1mg/ml(13.8 and 41.3 nmol Trolox equivalent) were not significantly different from those at the concentrations of 1 and $10mg/m{ell}$(11.4 and 41.2nmol Trolox equivalent), indicating that capsaicin showed 10 times higher ABTS radical scavenging activity compared to hot pepper extract. 3. ORAC of capsaicin at the concentrations of 1, 5, 10 and 100 mg/ml were 0.04, 0.17, 0.29 and 1.74nmol gallic acid equivalent, respectively. On the other hand, ORAC of hot pepper extract at the concentrations of 1, 5, 10 and $100{mu}g/m{ell}$ were 0.15, 0.44, 0.75 and 2.49nmol gallic acid equivalent, respectively, indicating that capsaicin showed higher peroxyl radical scavenging activity than hot pepper extract. 4. Inhibition of lipid peroxidation caused by hot pepper extract at the concentrations of 1 and $10mg/m{ell}$ were 12.2 and 61.4%, respectively. Inhibition of lipid peroxidation caused by capsaicin at the concentrations of 1 and $10mg/m{ell}l$ were 64.0 and 96.8%, respectively. Thus capsaicin showed 10 times stronger effect in inhibiton of lipid peroxidation than hot pepper extract. 5. Total phenolic contents of hot pepper extract at the concentrations of 0.1 and $1mg/m{ell}$ were 1.4 and 20.8nmol gallic acid equivalent, respectively. Total phenolic contents of capsaicin at the concentrations of 0.1 and $1mg/m{ell}$ were 6.1 and 55.4 nmol gallic acid equivalent, respectively, indicating that capsaicin had 2.7 to 4.3 times higher total phenolic contents than hot pepper extract. Conclusions : In summary, the results of this study demonstrate significant antioxidant activity of hot pepper extract, although the activity was lowered compared to capsaicin, suggesting that hot pepper extract play a role in prevention of oxidative-related diseases.