Septic arthritis of the temporomandibular joint as a complication of acute otitis media is rare in the Western world. This report describes the case of a 7-year-old boy who had pain in his right ear and limited mouth opening, following the onset of acute otitis media. A contrast-enhanced computed tomography scan revealed right-sided mastoiditis and hydrops of the right temporomandibular joint, suggesting septic arthritis. Real-time PCR and microbiologic analysis identified Streptococcus pyogenes and Staphylococcus epidermidis in the joint aspirate. Treatment with arthrocentesis and antibiotics led to full recovery of temporomandibular joint function. Schlagwörter: acute otitis media, arthrocentesis, diagnosis septic arthritis, mastoiditis, real-time PCR, Streptococcus pyogenes, temporomandibular joint, therapy