There are free, evidence-based Digital Health Interventions (DHIs) that can help children’s mental health, but few parents use them. We sought to understand what influenced uptake of DHIs by parents of children aged 2-12 years old with a mental health problem. We interviewed parents and analysed data using inductive content analysis. Four factors emerged: i) personal capacity; ii) awareness of DHIs and where to find one; iii) credibility, including trust and endorsement from experts; and iv) the suitability of a DHI to their child’s specific problem and level of need. Incorporating these themes into the design of future DHIs may improve uptake.