Abstract: This study investigated the difference of antioxidant function increasing by peanut coat powder and onion powder in bread with different additive amount. The contents of total phenols and total monomeric anthocyanin were determined by Folin-Ciocalteu method and pH differential method,respectively. The hydroxyl radical scavenging activity,DPPH radical scavenging activity and total antioxidant activity of bread extractions were tested. The results indicated that the contents of total phenols and total monomeric anthocyanin,the hydroxyl radical scavenging activity,DPPH radical scavenging activity and total antioxidant activity of bread were greatly improved when the additive amount of peanut coat powder and onion powder was up to 5%. In all antioxidant function,DPPH radical scavenging activity had the most apparent improvement with the increase of additive amount. The content of total monomeric anthocyanin in peanut coat powder bread was higher than that of onion powder bread with the same additive amount. The hydroxyl radical scavenging activity and DPPH radical scavenging activity of peanut coat powder bread were both better than those of onion powder bread. When additive amount was up to 6%,the amplification of the contents of total phenols and total monomeric anthocyanin slowed down,and the antioxidant function dropped. Considering economy and antioxidant effect,the additive amount of peanut coat powder and onion powder should be 5%. The peanut coat powder showed better antioxidant function in bread than onion powder.