Pompe disease is a lysosomal storage disorder that results from an inborn error of metabolism which involves abnormal glycogen storage. Infantile-onset Pompe disease is the most severe phenotype that manifests with the findings of hypotonia, generalized muscle weakness, feeding difficulties, a failure to thrive, hearing loss, hypertrophic cardiomyopathy with systolic dysfunction, and respiratory distress. There is no effective treatment for Pompe disease and clinical control includes primary support health care. However, recent studies have reported that enzyme replacement therapy (ERT) can effectively decrease the symptoms or severity of the disease. The present study is a case report of a 24-day patient with infantile-onset Pompe disease who presented coughing and respiratory distress. The infant experienced fatigue during breastfeeding from the birth and developed dry and nonproductive coughs and perioral cyanosis from two weeks after the birth. The echocardiogram demonstrated left and right ventricular enlargement, mitral and tricuspid regurgitation, and pulmonary hypertension. After definitive diagnosis, the patient was administered with 20 mg/kg of alglucosidase 50 mg vial once every two weeks. He experienced significant improvement in body weight and echocardiogram and symptoms such as fatigue during breastfeeding and perioral cyanosis disappeared completely while he was under Myozyme treatment. In general, the observations confirmed the efficacy of Myozyme in a patient with infantile Pompe disease. Therefore, early diagnosis and quick treatment of Pompe disease with Myozyme can lead to acceptable outcomes, improve conditions, and finally, increase the chance of survival in these patients.