Bio-techniques such as genetic manipulation, marker-assisted selection, and identity test have largely facilitated the modern animal production practices. In the present study, we established a reliable and cost-effective molecular method of species identification for common farm animals. We first (re-)analyzed 179 mitochondrial 12S rRNA gene sequences of ten farm animal species to determine the intra-species and species-specific variations. The PCR-RFLP method was subsequently designed to identify these species by using endonucleases BshNI, ScaI, AluI, and BfaI. The poultry and livestock species were first discriminated by one double-digestion of both BshNI and ScaI, which generated different fragment patterns (325 bp and 115 bp for poultry vs. 364 bp and 76 bp for livestock). The ten species could be further discerned according to species-specific restriction pattern by subjecting to digestion of AluI and BfaI, respectively. Our approach would be more reliable by taking the intra-species variations into consideration and could be applied to species identity test, commercial fraud, and wildlife crime.