The present invention discloses a bamboo leaf antioxidant material (AOB) and its application. AOB is a yellow or brownish yellow powder or granules obtained from bamboo leaf, its main antioxidant component includes flavone, lactone and phenolic acid compound, the total flavone glucoside content determined by colourimetry is greater than or equal to 30%, total lactone content is greater than or equal to 15% and phenolic acid content is greater than or equal to 7.5%. It not only can be block the chain reaction of automatic oxidation of fat, but also can chelate trasition state metal ion, at the same time can be used as first-grade and second-grade antioxidant to produce action, and can effectively remove nitrite and can block synthesis of nitrosamine, and has the actions of resisting bacteria, inhibiting fungi, deodorization and increasing perfume, so that it has extensive application.