Head and neck swellings are common referrals to the otolaryngology department, with a wide range of aetiologies. Internal jugular vein thrombosis presenting as swelling in the neck is a rare occurrence. The authors report a case of bilateral internal jugular vein thrombosis secondary to malignant lymphadenopathy of unknown origin. The patient presented with a short history of a diffuse swelling in the neck with neck stiffness. Examination revealed palpable cervical and axillary lymphadenopathy. Causes of spontaneous internal jugular vein thrombosis were discussed.