Acute suppurative thyroiditis is a very rare and life-threatening endocrine emergency. Thyrotoxicosis is a rare condition accompanying acute suppurative thyroiditis. While the majority of the cases in the literature are caused by different reasons, spontaneous development is very rare. We present a patient with acute suppurative thyroiditis who presented to our clinic with thyrotoxic findings, and we compared the case to the literature. A 31-year-old male patient was admitted to our clinic with a complaint of progressive neck pain, swelling and redness on midline neck, fever, and palpitations. On physical examination, swelling, redness and tenderness were detected on the neck region that was consistent with the thyroid location. He presented with tremor on the hands, tachycardia and agitation. Thyroid function tests were compatible with thyrotoxicosis, but there were findings supporting the presence of infection in biochemistry tests. On his radiological evaluations, a heterogeneous lesion divided with small septs was observed, with consolidation areas in the left thyroid lobe. In fine needle aspiration biopsy, 2mL of purulent fluid could be aspirated due to the presence of small, separated consolidation areas. He initiated on antibiotic therapy, propranolol, steroid and symptomatic treatment. Eikenella corrodens was detected on the culture antibiogram. Antibiotic therapy was continued for 14 days due to less symptoms and better biochemical values. After treatment, the patient had normal thyroid function, had relief of fever and redness of the neck, and was followed-up. It should be kept in mind that acute suppurative thyroiditis may develop spontaneously with the findings of thyrotoxicosis, with no risk factors.