Multiple exostosis is associated with the autosomal dominant disorder and hereditary multiple exostoses (HMEs), are rarely growing around the ribs and the formation of a large lump into the thoracic cavity. It's generally agreed that when there are no symptoms present, a HME patient could either avoid any treatment or postpone the operation until adolescence. We present a 5-year-old boy with 4 cm × 3.5 cm HMEs lump invasion into the thoracic cavity, with symptoms of chest distress and right chest pain. This patient received video-assisted thoracoscopic surgery (VATS) and a the lump and 1 cm rib involved was resected. During a 2 years follow-up, the patient remained in good condition without recurrence and complications.