Field surveys in Taiwan have uncovered turtles presumed to be hybrids based on their intermediate morphology. We sequenced a mitochondrial (ND4) and nuclear (R35) gene of two putative hybrid individuals, along with representatives of the potential parental species ( Mauremys mutica , M. reevesii , M. sinensis ), to determine their genetic identity. Based on our data, both individuals are hybrids, with independent, recent origins resulting from the mating of a female M. reevesii and a male M. sinensis . Since we question whether the highly traded M. reevesii is endemic to Taiwan, this hybridization could represent human-mediated genetic pollution. We also discuss the implications of our findings on turtle conservation in Taiwan.