Background/Objectives: Male breast cancer (MBC) is a rare malignancy with a globally rising incidence. Due to the paucity of specific evidence, therapeutic strategies are often extrapolated from female breast cancer guidelines. The quality of life (QoL) among MBC patients remains underexplored. Methods: This single-institution retrospective study analyzed male patients who underwent surgery for newly diagnosed breast cancer at our institution from 1998 to 2020. The primary aim was to assess QoL after surgical and medical treatments using a newly developed 12-item dedicated questionnaire. Clinicopathological features were recorded, and oncological and survival outcomes were evaluated, with a specific focus on identifying factors influencing QoL. Results: A total of 109 consecutive MBC patients who underwent surgery were included, with 96.3% undergoing total mastectomy. The median global QoL score was 28.5 out of 36, where scores above 24 indicated a low impact of BC treatments on QoL. Multivariate analyses identified adjuvant chemotherapy (p < 0.001) and postoperative complications (p < 0.001) as significant predictors of poorer QoL. Patients reported significantly lower scores on medical treatment-related items compared to surgery-related items (p < 0.001). The 10-year overall survival rate was 79.1%, with a 10-year BC-specific mortality of 3.5%. Advanced age, higher stage disease, and receiving adjuvant chemotherapy were independently associated with poorer overall survival. Conclusions: Despite elevated mastectomy rates, MBC patients self-reported high levels of satisfaction with their treatment outcomes. Medical therapies showed a more pronounced negative impact on QoL than surgery. These findings provide novel insights into the QoL of MBC patients, highlighting the need for future prospective studies and tailored treatments.