A high performance liquid chromatography-UV method is established for the determination of 16 sulfonamides residues in milk and powder milk clean up by immunoaffinity column (IAC) . After extraction with ethyl acetate, the clear part is loaded on the IAC column for purification, the mobile phase is methanol-1.1% acetic acid-0.01 mol PBS with gradient elution, and the chromatographic analysis is performed by HPLC. The recoveries of the method are in the range of 80%- 110%, the RSD is below 10%, the limit of quantification for mil...