Internal Jugular vein (IJV) thrombosis is a rare entity. It is usually secondary to various etiologies such as catheter, malignancy, trauma, infection and hypercoagulable status. Associated malignancies, either known or occult, are also uncommon and not well documented in the etiology of IJV thrombosis. We reported IJV thrombosis with two different pathologies i.e. malignacy and congestive heart failure. The diagnosis of IJV thrombosis was established with Doppler ultrasound and CT scan. These patients were treated low-molecular-weight heparin and oral anticoagulation. Early diagnosis and appropriate management is important to prevent potentially fatal complications from internal jugular vein thrombosis.