Abstract: The extraction of peptides from oat and its antioxidant property and inhibition to α-amylase were investigated. Based on the single factor experiments, the orthogonal design was used to optimize hydrolytic condition. The results showed that optimization hydrolytic conditions were as follows:pH7.5, solid-liquid ratio 1∶ 14, temperature 60℃, and adding amount of enzyme 6%, from which the DPPH scavenging rate was 80.11%, Fe2+chelating ability of 1.8mg/mL oat peptides was 60.24%, and hydroxyl radical (·OH) scavenging rate of 3.2mg/mL oats peptides was 49.15%. The α-amylase inhibition activity of two fractions obtained from ultrafiltration were compared and the results showed that the α-amylase inhibition activity of 5mg/mL>5ku oat peptide and 5mg / mL < 5ku oat peptide were 51. 06 % and 68. 98 %. The optimized α- amylase inhibition conditions were as follows:concentration of substratum 90mg/mL, concentration of peptides 12mg/mL, inhibitive time 10min. The antioxidant and α-amylase inhibition activities of oat peptides make it suitable for development of functional food.