Carotid body tumor (CBT), also referred to as paraganglioma, has mitochondrial succinate dehydrogenase (SDH) gene mutation, including SDHD, SDHC and SDHB gene mutation. SDH gene mutation mainly occurred in familial CBT patients, seldom in sporadic cases. Researches in the relationship between CBT and SDH gene would provided a new approach for tumor genesis, gene diagnosis, genetic consulting and therapy of CBT.