A 35 years old man and a 76 years old woman having a carotid body tumors are presented. The carotid body tumor is an uncommon pathological appearance. The difficulty of making preoperative diagnosis of a carotid body tumor comparing with other similar tumors which occurred on neck region is discussed. For the early discovery of this tumor and to determine the operability, the arteriography is stressed as the most useful diagnostic aid. The first case has good result after operation but the other case was expired 5 days after operation.