PURPOSE: Men with advanced prostate cancer experience a wide range of side effects from the cancer and its therapies, which have a negative effect on their quality of life (QOL). Few studies have evaluated supportive care needs in these individuals. The purpose of this study was to conduct a holistic supportive care needs assessment among these survivors guided by the Supportive Care Framework for Cancer Care. METHODS: Using a convergent parallel mixed-methods approach, prostate cancer survivors with advanced disease (n = 188) completed a cross-sectional survey. A subset of these survivors (n = 20) participated in an interview to further explore their experience of unmet needs. RESULTS: Survivors reported unmet supportive care needs in every domain of the framework. Up to 95.2% of the survivors had at least one unmet need, with a mean of 14.9 (range: 0-42). Several areas of convergence among the quantitative and qualitative data (fatigue, sexual dysfunction, practical, and emotional/psychological domains), as well as divergence (informational and spiritual domains, depression, urinary dysfunction) were found through the integration process. CONCLUSIONS: This study confirms that prostate cancer survivors with advanced disease experience high rates of unmet supportive care needs. The findings also highlight the diversity of those unmet needs. These results may assist with future development of patient-centered supportive care interventions that better meet the specific needs of this vulnerable group of cancer survivors.