A multiresidue liquid chromatography/mass spectrometry (LC/MS) confirmation procedure for tetracyclines in milk was modified to confirm oxytetracycline (OTC) residues in shrimp. OTC was extracted from ground shrimp homogenate using metal chelate affinity chromatography (MCAC). The MCAC extract was desalted and further concentrated using polymeric solid phase extraction. OTC was resolved from matrix interferences on a polymeric reversed phase column and analyzed by methane negative ion chemical ionization on a Hewlett-Packard 5989A mass spectrometer using a particle beam LC/MS interface. OTC residues were monitored by scanning from m/z 378 to m/z 483. Confirmation was achieved by comparison of spectra obtained from shrimp extracts with spectra from external standards. The MCAC process provided a very clean and concentrated extract. PB-LC/MS analysis of the extracts resulted in a very high level of confidence in the specificity of residue identification.