BackgroundDespite disproportionate rates of mental ill-health compared with non-Indigenous populations, few programs have been tailored to the unique health, social, and cultural needs and preferences of young Aboriginal and Torres Strait Islander males. This paper describes the process of culturally adapting the US-based Young Black Men, Masculinities, and Mental Health (YBMen) Project to suit the needs, preferences, culture, and circumstances of Aboriginal and Torres Strait Islander males aged 16–25 years in the Northern Territory, Australia. YBMen is an evidence-based social media-based education and support program designed to promote mental health, expand understandings of gender and cultural identities, and enhance social support in college-aged Black men.MethodsOur adaptation followed an Extended Stages of Cultural Adaptation model. First, we established a rationale for adaptation that included assessing the appropriateness of YBMen’s core components for the target population. We then investigated important and appropriate models to underpin the adapted program and conducted a non-linear, iterative process of gathering information from key sources, including young Aboriginal and Torres Strait Islander males, to inform program curriculum and delivery.ResultsTo maintain program fidelity, we retained the core curriculum components of mental health, healthy masculinities, and social connection and kept the small cohort, private social media group delivery but developed two models: ‘online only’ (the original online delivery format) and ‘hybrid in-person/online’ (combining online delivery with weekly in-person group sessions). Adaptations made included using an overarching Aboriginal and Torres Strait Islander social and emotional wellbeing framework and socio-cultural strengths-based approach; inclusion of modules on health and wellbeing, positive Indigenous masculinities, and respectful relationships; use of Indigenous designs and colours; and prominent placement of images of Aboriginal and Torres Strait Islander male sportspeople, musicians, activists, and local role models.ConclusionsThis process resulted in a culturally responsive mental health, masculinities, and social support health promotion program for young Aboriginal and Torres Strait Islander males. Next steps will involve pilot testing to investigate the adapted program’s acceptability and feasibility and inform further refinement. Keywords: Aboriginal, Torres Strait Islander, Indigenous, Australia, male, cultural adaptation, social media, mental health, masculinities, social support.