Objective <p>This study investigated whether camouflaging had an impact on the internalizing and externalizing mental health characteristics of autistic children and adolescents, and if internalizing symptoms influenced the relationship between camouflaging and externalizing symptoms.</p> Methods <p>The study examined the effects of camouflaging on mental health in a matched sample of 331 female and 331 male autistic children and adolescents. Discrepancy scores between clinician-administered assessment and parent report were calculated, and these facilitated regression and mediation analyses.</p> Results <p>Results indicated that camouflaging predicted internalizing symptoms (e.g., anxiety, depression, and somatic complaints) and externalizing symptoms (e.g., rule breaking and aggression), even when controlling for age, sex, and IQ. Furthermore, findings indicated that internalizing symptoms mediated the relationship between camouflaging and externalizing symptoms.</p> Conclusions <p>These findings highlight the importance of parents being included in clinical research and assessment and provide further insight into potential mechanisms that underlie the mental health vulnerabilities of autistic children and adolescents.</p>