Large-cell neuroendocrine carcinoma of the thymus is a rare cancer that is more aggressive than other thymic epithelial tumors with poorer prognosis. We report one such case in a 44-year-old male patient with invasion into the upper 2/3rd of the sternum but no endocrinopathy. Complete enbloc resection of the tumor with adherent pericardium, upper 2/3rd of the sternum and mediastinal lymphadenectomy was performed. The chest wall was reconstructed with polypropylene mesh and bilateral pectoralis major muscle advancement flap cover. A search of PubMed database with user query words 'neuroendocrine carcinoma, thymus gland, sternal invasion' revealed no case report in the literature of thymic neuroendocrine carcinoma with invasion of the sternum.