The patient, a 56-year-old female, was admitted to the hospital on April 12, 2010, mainly because of a painless swelling in the right submandibular region for six months. Six months ago, a right-sided neck mass was found unintentionally, which was soft and intermittently tingling, often appearing at night and lasting for a few minutes. He was seen at a local hospital and ultrasound examination showed an occupying mass in the right submandibular region. Previously, he was in good health. Physical examination showed a good general condition. Specialist examination showed an elevation of the right submandibular region and the upper part of the sternocleidomastoid muscle with normal surface skin color. Palpation showed an enlarged right submandibular gland with a mass of about 3×4×3 cm, which extended toward the carotid triangle with unclear borders, tough texture, insignificant activity, and no pulsation. Ultrasound examination: a 3.9×3 cm solid isoechoic mass with clear borders and abundant arteriovenous blood flow signal was detected in the right submandibular region and its carotid triangle. CT examination: a mass-like soft tissue shadow was seen at the level of the flat hyoid bone in the right carotid space, with uneven density and unclear borders, with a maximum dimension of about 37.3×30,4. Preliminary diagnosis: the nature of the right cervical mass was to be investigated. Treatment: excision of the right cervical mass was performed under general anesthesia. Intraoperatively, the mass was seen to be located at the bifurcation of the carotid artery, riding on the bifurcation of the carotid artery and encircling part of the common carotid artery, the internal carotid artery and part of the external carotid artery. It was dark red, soft in texture, with still clear borders, and bleeding easily during separation. It was diagnosed as a carotid body aneurysm. Then, 2000 ml of blood was prepared and the unencircled common carotid artery, internal carotid artery and external carotid artery were firstly separated and surrounded by rubber bands. Then the common carotid artery was blocked, and the aneurysm was gradually and rapidly separated from the arterial wall. The artery was broken during the separation of the internal carotid artery, so a repair anastomosis was performed. After checking that there was no bleeding, a rubber drainage piece was placed and intermittently sutured in layers. Postoperative management: The rubber drain was removed 24 hours after surgery, and the wound was bandaged with pressure. The wound was discharged in 7 days after stitches were removed and healed.