The invention relates to a magnetic immunochemiluminescence kit for detecting lincomycin, which comprises the following reagents, enzyme-labelled antigen, an enzyme-labelled antigen weak solution, a magnetic antibody, a magnetic antibody weak solution, a lincomycin series standard substance solution, a chemiluminescence substrate solution A, a chemiluminescence substrate solution B, a concentrated compound solution, and a concentrated washing liquid. enzyme-labelled antigen is a horseradish peroxidase-labelled lincomycin hapten marker, lincomycin hapten is keto lincomycin obtained by performing pyridinium dichromate cas oxidation on alcoholic hydroxyl group from lincomycin, keto lincomycin and aminobutyric acid are subjected to a condensation reaction to obtain four-carbon chain carboxyl hapten, the magnetic antibody is obtained by coupling the lincomycin monoclonal antibody and magnetic bead. The invention also relates to a method for detecting lincomycin in milk and milk powder by employing the kit and a matched chemiluminescence detector, and the method has advantages of high sensitivity, specificity and short detection time for detecting lincomycin.