PURPOSE: The purpose of this study is to analyze the CT features of the cystic masses in the neck and to review differential diagnosis. MATERIALS AND METHODS: We retrospectively reviewed and analyzed the CT findings of 22 histopathologically proved, cystic neck masses in regard to the location in fascial plane and relationship with adjacent organ. RESULTS: Of 22 cases, ten congenital cysts two ranulas, seven inflammatory lesions, and three solid tumors were includded. Ten congenital cystic masses were located in typical locations as branchial cleft cyst(5) in mandibular angle, thyroglossal duct cyst(3) in visceral space embeded within the strap muscles, cystic hygroma(1) and cavernous hemangioma(1) in posterior cervical space with insinuating appearance. Two cases of ranula included one simple ranula localized in sublingual space and a plunging ranula extending to adjacent submandibular space. Seven cases of inflammatory lesions were characterized by multispatial locations and good contrast-enhancement of walls and adjacent tissue. Solid masses of low density mimicking cyst were two pleomorphic adenomas of submandibular gland and one neurilemmoma. CONCLUSION: It is considered that thorough analysis of the CT findings with attention to typical location, CT appearance, and the relationship with the adjacent structures usually leads to the correct diagnosis.