Male breast cancer is a rare disease, accounting for less than 1% of all breast cancer cases. It is often diagnosed late, at a more advanced stage than its female counterpart. Therefore, it is more commonly treated with mastectomy. In early stages, a conservative treatment associating lumpectomy, sentinel lymph node (SLN) biopsy and whole-breast external beam radiotherapy (EBRT) is possible and has been described. Recently, intra-operative radiation therapy (IORT) has been assessed as an alternative to EBRT in selected female breast cancer cases. Its use has never been described in male patients. In this article, we present the case of a 56 years old man treated with lumpectomy with the excision of the nipple-areola complex, SLN biopsy, and IORT with electron beams (IOERT), for early breast cancer disease. This case demonstrates that the IORT technique is feasible on men with early breast cancer (pT1N0).