Kawasaki disease, also known as mucocutaneous lymph node syndrome, is an acute febrile rash disease characterized primarily by inflammation of medium and small arteries throughout the body, with a self-limiting nature. Clinically, it mainly presents with fever, rash, mucosal lesions, conjunctival congestion, and non-suppurative enlargement of cervical lymph nodes. If untreated, 20% of cases can lead to coronary artery damage. To diagnose this disease, in addition to typical clinical manifestations, attention must also be paid to various tests such as blood tests, immunological tests, and ultrasound examinations for a comprehensive assessment. Although the clinical characteristics are largely indicative of the disease, ultrasound examination is crucial to check for any dilation of the coronary arteries.