Mental health difficulties are prevalent among autistic adults. Camouflaging (behaving differently to fit in) may be a mechanism by which autistic traits and mental health difficulties relate to each other, but little research has considered the role of different facets of camouflaging. Additionally, autistic identity might buffer against camouflaging and mental health difficulties. This research aims to explore the mediating effects of camouflaging behaviours on the relationship between autistic traits and both positive and negative mental wellbeing, as well as how autistic identity might moderate the relationship between autistic traits and camouflaging, and also mental health. Data were available for 627 autistic adults, recruited through volunteer databases and social media. Participants completed measures of autistic traits, anxiety, depression, positive wellbeing, camouflaging behaviours (compensating for difficulties, masking, and assimilating/putting on an act) and autistic identity. Mediation and moderated mediation models were tested, applying 95% bootstrapped CIs (10,000 resamples) and including age, gender and diagnosis as covariates. There were no significant direct effects between autistic traits and mental wellbeing. Assimilation was a significant mediator of all mental wellbeing measures, and compensation was a significant mediator of positive wellbeing only. Autistic identity was not a significant moderator. Assimilation and compensation should be considered when offering psychological interventions to support mental wellbeing of autistic people. Additional research into external drivers of camouflaging (e.g. stigma) and mechanisms by which camouflaging impacts mental wellbeing, such as autonomy, authenticity, skill mastery and community, may identify other areas of support. Concurrently, societal change is necessary to reduce the need to camouflage.