Lemierre syndrome is a rare disease that is defined by a pharyngeal infection, complicated by septicemia and internal jugular vein thrombosis followed by septic emboli. Because of its rarity, a delay in diagnosis is not uncommon. However, given the mortality rate of approximately 2%, prompt diagnosis and detection of septic emboli are essential to initiate prompt treatment, preventing organ damage and ongoing sepsis. We present 3 cases that demonstrate the value of FDG-PET/CT as a possible alternative or adjunct to conventional imaging methods for diagnosis and whole-body evaluation of Lemierre syndrome.