Lemierre syndrome, also known as postanginal sepsis, is a severe complication of an acute oropharyngeal infection that result in septic thrombophlebitis of the internal jugular vein with subsequent septicemia. This disease is relatively rare, but it has significant morbidity and is potentially fatal. Early diagnosis based on computed tomography with contrast enhancement is mandatory and immediate treatment including intravenous antibiotics, anticoagulants, or surgical approach should be considered. We report a case of Lemierre syndrome after deep neck infection which was successfully treated using antibiotics and anticoagulants.