We reported a 12-year-old boy with Emery-Dreifuss muscular dystrophy (EMD). He was born after uncomplicated full term pregnancy and delivery. There was neither consanguinity nor a history of neuromuscular disorders or cardiac diseases in his family. He walked at 14 months. Toe walking was recognized at age 5 years. Examination at age 12 years showed the following. He could walk and climb stairs. There was no Gowers' sign. He had mild weakness of muscles except for face muscles. He had joint contractures at heels, elbows and knees. Deep tendon reflexes could not be elicited. Serum creatine kinase activity was significantly raised. Electromyography showed a myogenic pattern. Muscle biopsy from the left quadriceps showed mild dystrophic changes. 24 h Holter monitoring showed atrioventricular block with Wenckebach phenomenon. Prognosis in EMD is strongly connected with cardiac involvement. Therefore, we must follow up this case carefully for cardiac symptoms.