A study utilising data from the Youth19 Rangatahi Smart Survey has highlighted the importance of safe and inclusive green space for promoting mental health and mitigating health inequalities of adolescents in urban areas. A total of 3813 adolescents living in Auckland were included in the study. Results showed that perceived neighbourhood safety plays a vital role in the association between green space accessibility (GSA) and mental wellbeing, with a negative trend in adolescents who reported being less safe in neighbourhoods. Marginalised adolescents tended to feel less safe in neighbourhoods, had lower emotional wellbeing and a higher level of depressive symptoms. There were inequalities in GSA for adolescents who lived in the most deprived neighbourhoods and for adolescents of Māori ethnicity.