Fusobacterium necrophorumis a Gram-negative anaerobic bacterium that can lead to severe infection in young patients even without immunodeficiency. Due to the length of time for isolation and speciation of this Gram-negative bacillus (typically 5–8 days), and its potential mortality, broad-spectrum antibiotic therapy should be started without delay. With a cervical thrombosis, even on an unusual site and with a standard condition such as tonsillitis, Lemierre syndrome should be considered. We report a case of Lemierre syndrome in a previously healthy young woman.