Background: There is increasing interest in the experiences and well-being of siblings growing up with a brother or sister with a disability in Australia. However, research to date has primarily obtained parent reports of sibling adjustment and mental health. Therefore, the aim of the current study was threefold: (1) to report on the mental health of siblings using a self-report version of the Strengths and Difficulties Questionnaire (SDQ); (2) to compare sibling mental health with Australian normative data on the SDQ; and (3) to identify socio-demographic and disability characteristics associated with sibling mental health difficulties. Methods: Participants were 52 siblings (aged 10-18 years) of children with varying disabilities. Results: Although siblings reported significantly more emotional and behavioural problems than a normative sample, the majority of siblings reported overall good mental health within the normal range on all SDQ subscales. Approximately 20-30% of siblings were identified as at-risk or in the clinical range for overall difficulties, hyperactivity-inattention, conduct and peer problems; and 15% at-risk or in the clinical range for emotional symptoms and prosocial behaviour. Socio-demographic and disability characteristics were not associated with mental health difficulties. Conclusions: A small proportion of siblings are at risk of emotional and behavioural problems. Implications for future research, policy, and clinical practice are discussed. (Contains 3 tables.)