About 8% of all children and adolescents worldwide are affected by chronic diseases. Managing chronic conditions requires pediatric patients to be health literate. The purpose of this review is to examine the existing evidence on the links between health literacy and its outcomes proposed by the model by Sørensen et al. in chronically ill pediatric patients. Four electronic databases (PubMed, Scopus, CINAHL, PsycINFO) were searched to identify pertinent articles published up to November 2021. The search was conducted independently by two researchers and restricted to observational studies. Of 11,137 initial results, 11 articles met eligibility criteria. Overall, 6 studies identified a significant association between health literacy and one of the considered outcomes. Regarding health behavior, none of the studies on adherence found significant associations with health literacy. The results in terms of health service use were inconclusive. Regarding health outcomes, health literacy did not affect most physiological parameters, but it significantly improved health-related quality of life. Overall, evidence remains inconclusive but suggests that health literacy is associated with self-efficacy, health-related quality of life, and health service use in pediatric patients. Further research should be undertaken to strengthen the evidence.