Abstract Background Septic arthritis of the temporomandibular joint (TMJ) is rare. It usually causes isolated, locoregional symptoms related to the infected intra-articular space but may also cause fever and malaise. Case report We present a case of a 72-year-old male with septic arthritis of the TMJ complicated by extensive peri-articular necrosis, septic shock, cerebral abscess, Lemierre’s syndrome, and a pathological fracture of the mandibular condyle. Conclusion Case reports describing such a severe course of the disease are few. Moreover, this is the first report of septic arthritis of the TMJ to cause Lemierre’s syndrome.