Purpose: The number of informal caregivers to cancer survivors is increasing, and limited information is available about caregivers to sexual minority breast cancer survivors. The purpose of this study was to assess dyadic quality of life among sexual minority cancer survivors and their caregivers compared with heterosexual cancer survivors and their caregivers.; Methods: We recruited 167 survivors of non-metastatic breast cancer of different sexual orientations and their caregivers, who were surveyed via telephone after obtaining consent.