Background <p>Prostate cancer treatment can lead to significant long-term side effects that impact patients’ quality of life and supportive care needs (SCN). This study explores the associations between quality of life (QoL) and SCN among prostate cancer survivors, with a focus on the impact of treatment received, care service utilization, and the differences between Māori and non-Māori patients.</p> Methods <p>Random stratified sampling data were collected from 1075 prostate cancer survivors who were diagnosed within the past 5&#xa0;years. Hierarchical regression analyses examined the associations between QoL domains and SCN, adjusting for demographic, clinical, and treatment-related factors. LASSO (Least Absolute Shrinkage and Selection Operator) was used to select variables to test the interaction effects of different treatments.</p> Results <p>Significant disparities were found between Māori and non-Māori patients in physical and mental health scores, care service utilization, and overall SCN. Māori men had lower scores in these areas. Most QoL domains were negatively associated with more SCN, particularly mental health and hormonal issues. Androgen deprivation therapy (ADT) exacerbates some negative effects of poor mental health and hormonal issues for non-Māori, while the use of care services and radical prostatectomy (RP) was associated with mitigating SCN for Māori patients.</p> Conclusion <p>This study highlights the complex interplay between QoL, SCN, and treatment modalities among prostate cancer survivors in New Zealand. The findings underscore the need for culturally tailored supportive care services to address the unique needs of Māori patients.</p>