This standard specifies the high performance liquid chromatography method for the determination of benzoic acid and sorbic acid in feed. This standard is applicable to the determination of benzoic acid and sorbic acid in compound feeds, concentrated feeds, additive premixed feeds and concentrate supplements. The detection limit of this standard: both benzoic acid and sorbic acid are 20mg/kg. The quantification limit of this standard: both benzoic acid and sorbic acid are 50mg/kg.