Lemierre’s syndrome usually developes after an episode of acute upper respiratory infection. Fever, sore throat and neck pain are not specific symptoms and are usually treated as acute pharyngitis or tonsillitis. However, septic thrombophlebitis of the internal jugular vein with septic emboli that cause metastatic infections may make this disease complicated and fatal. We present a 28-year-old man who was initially diagnosed with acute tonsillitis and suspect EBV infection. After further evaluations, he was finally diagnosed with Lemierre’s syndrome and was treated successfully.