ObjectiveTo outline the clinical signs, diagnosis, and course of care for a single case of neonatal hyperthyroidism while also summarizing common diagnostic errors related to this condition.MethodsMedical records of the neonate of hyperthyroidism were collected and analyzed in combination with literature.ResultsThe neonate's mother had thyroid disease, but her thyrotropin receptor antibody (TRAb) levels were not monitored during pregnancy. The neonate exhibited typical symptoms of hyperthyroidism on the day of birth but was not diagnosed until 15 days later. Impaired liver (cholestasis, elevated liver enzymes) and cardiac function (pulmonary hypertension, right heart enlargement) are the main manifestations. Treatment with methimazole (1.0 mg /kg center dot d) and propranolol (2.0 mg /kg center dot d) led to recovery, and the neonate stayed in the hospital for 27 days before being discharged with medication. The diagnosis was temporary hyperthyroidism, and the medication was discontinued at 72 days of age.ConclusionIt is important to strengthen the management of high-risk pregnant women with thyroid disease. Monitoring TRAb levels in both mothers and neonates should be done dynamically to enable early prediction and diagnosis of neonatal hyperthyroidism. Most neonates with hyperthyroidism have a good prognosis when timely and appropriate medical treatment is provided. The tortuous diagnosis processes of one case of NH.In the absence of specific clinical manifestations of NH, how to quickly diagnose it.Reminding clinicians of the importance of early identification of NH, as well as the management of pregnant women with abnormal thyroid function.