ObjectiveTo investigate antibiotic decomposition of raw milk β-lactamase residues in milk samples of commercially availability in Nantong, and to provide the basis for reasonably controlling β-lactamase added in milk. MethodsTo test β-lactamase in milk samples employing "sulbactam sensitive β-lactamases drug test method-cup method, in milk and milk products" published by Ministry of Health. ResultsAmong 102milk samples from 5manufactures, β-lactamase was detected in 15samples (relevance ratio:14.7%) from 2factories. The differences between bacteriostatic ring of 15positive samples were among 3.9-17.9mm. Conclusionβ-lactamase adding residues are available in commercial milk products in the market of Nantong, and some residues are tremendous, which would make food safety hazards to some extent. So it''s necessary to enhance administration and control.\=