Cervicothoracic cystic lymphangiomas are found commonly in children less than 2 years of age, but the same are rare in adults. These form as a result of abberant development of embryonic lymph sac which is gradually filled with lymph fluid.1 They are commonly found in the head and neck region but can be present anywhere in the body. Preoperative diagnosis is based on careful history of a soft, painless, fluctuant, gradually enlarging mass and imaging. Surgery constitutes the basis of treatment and provides postoperative confirmation of diagnosis via histology. We, here report a case of cervicothoracic cystic lymphangioma in a 24-year male. The rationale of reporting this case is to discuss its presentation, diagnosis and surgical management. Moreover, we also want to highlight its scarcity in adults, the swelling being a diagnostic challenge and role of histology in affirmative diagnosis.