AIM: This research investigated the mental health of mothers of school-aged children with disabilities in Victoria, Australia. METHODS: A mixed method triangulation design model was used to investigate the mental health of mothers (n= 152) of school-aged children with developmental disabilities. Self-reported medical history and completion of the Short Form Health Survey Version 2 were used to collect data via mail-out survey and follow-up phone interview. RESULTS: Mothers reported subjective mental health two standard deviations below other Australians and higher rates of depression and anxiety that other Australian women and the adult population in general. Half of participants reported that their health affected their ability to provide the care that their child needed, and half experienced frequent interrupted sleep secondary to the care of their child with a disability. Significantly poorer mental health was reported by mothers with a pre-school-aged child as well as a child with a disability (P < 0.001), mothers with more than one child with a disability (P= 0.038), mothers of children with autism spectrum disorder (ASD) (P= 0.026), and mothers who recognised that their health affected care giving (P < 0.001). CONCLUSIONS: The reported mental health of participants in this study indicates that further attention is needed to action health strategies to support mothers of children with disabilities. Health programs and policy that will identify mothers in need of assistance, as well as management strategies that will adequately support mental wellness in mothers is required in Australia.