Background <p>The aim of this study was to develop a web-based psycho-educational intervention for parents of adolescents with anorexia nervosa and carry out a mixed method evaluation of its acceptability and feasibility.</p> Methods <p>After developing the intervention, we recruited parents from 19 families of adolescents with AN engaged in family-based therapy at an outpatient specialist center for eating disorders. Participants were given 6-month access to the intervention. Acceptability, feasibility, parental well-being and mental health, and family functioning were collected at baseline and again three months after baseline.</p> Results <p>Among the 11 parents from families who participated and accessed the intervention, the majority rated the intervention as satisfying (median = 6, IQR = 5–7), and easy to use (median = 7, IQR = 6.5–8.3). Frequency of use was about once a month. No significant differences between baseline and follow-up were found for parental well-being and mental health. We observed an increase in parental self-efficacy with a large effect size (<i>p</i> = 0.07, rs = -0.52), suggesting a potentially meaningful association. Parents identified positive aspects of the intervention as ease of access, comprehensive content and a positive impact on their approach to their child’s illness.</p> Conclusions <p>This study suggests that an add-on digital intervention to family-based treatment for parents of adolescents with AN is acceptable and feasible. Satisfaction, ease of navigation, and finding answers to questions were positively rated. Web-based or computerized psychoeducation for parents can be a valuable addition to treatment for adolescent AN.</p>