Mitochondrial cytochrome oxidase III(COIII) of duck was successfully amplified by PCR-mtDNA with duck muscle DNA as the template (GenBank Accession No. DQ655706). Cloning sequence analysis shows that the 784 bp nucleotides of COIII gene were contained. Through homology analysis, we confirmed that the cytochrome oxidase III(COIII) was relatively conservative. The method of PCR-mtDNA can be designed to detect the components of duck origin. And then, the method of PCR can be applied to amplify with the muscle DNA of various animal and feedstuff as the template, repeated verification, the primer ( P3, P4 ) with strong specificity and good stability is screened, which can only amplify the sequence of duck. The special sequence contains 226bp, the amplified product of 226 bp was sequenced and analyzed, it showed 100% homology with duck mtDNA COIII gene, which proved the accuracy of the special primer. The test that used different concentration of DNA with P3 and P4 is the sensitive experiment by PCR. The result showed that the primer has much specialty and rather sensitivity. So it is a way to detect the duck origin in the muscle of various animal and feedstuff.