More than 25% of all children grow up with a chronic disease. They are at higher risk for developmental and psychosocial problems. However, children who function resiliently manage to adapt positively to these challenges. We aim to systematically review how resilience is defined and measured in children with a chronic disease. A search of PubMed, Cochrane, Embase, and PsycINFO was performed on December 9, 2022, using resilience, disease, and child/adolescent as search terms. Two reviewers independently screened articles for inclusion according to predefined criteria. Extraction domains included study characteristics, definition, and instruments assessing resilience outcomes, and resilience factors. Fifty-five out of 8766 articles were identified as relevant. In general, resilience was characterized as positive adaptation to adversity. The included studies assessed resilience by the outcomes of positive adaptation, or by resilience factors, or both. We categorized the assessed resilience outcomes into three groups: personal traits, psychosocial functioning, and disease-related outcomes. Moreover, myriad of resilience factors were measured, which were grouped into internal resilience factors (cognitive, social, and emotional competence factors), disease-related factors, and external factors (caregiver factors, social factors, and contextual factors). Our scoping review provides insight into the definitions and instruments used to measure resilience in children with a chronic disease. More knowledge is needed on which resilience factors are related to positive adaptation in specific illness-related challenges, which underlying mechanisms are responsible for this positive adaptation, and how these underlying mechanisms interact with one another.