Genomic mutation may be key factors for sex-biased disparities in cancer diagnosis, prognosis and prediction of treatment response. Current study has revealed that sex-based dimorphism on the efficacy of immune checkpoint inhibitors (ICIs) in various cancers and confirmed that male patients can benefit more from immunotherapy. However, only a subset of male patients responds well to ICIs. Therefore, biomarkers are desperately needed to identify the group of patients who may be more likely to benefit from ICIs. With the availability of the cBioPortal database, we identified that TERT mutation may serve as a sex-specific cancer biomarker and TERT mutation frequency of melanoma was higher in male patients. Notably, we found that male patients with TERT mutation may be more likely to benefit from immunotherapy (p = 0.006), especially for melanoma (p < 0.001). Therefore, our research provides a possible direction for the exploration of immunotherapy prediction biomarkers based on sex difference.