Basal cell carcinoma (BCC) of the prostate is a rare and enigmatic tumor with uncertain biological behavior and treatment modalities. Some studies suggest that BCC exhibits invasive characteristics and a high degree of malignancy, necessitating proactive management and vigilant monitoring. Notably, there is a lack of reported effective treatment utilizing programmed cell death protein-1 (PD-1) inhibitors for advanced BCC of the prostate. This study explores the efficacy of tislelizumab, as a single-agent therapy, in the successful treatment of advanced prostate BCC.