Purpose <p>In recent years, children in Mediterranean countries have shown low adherence to Mediterranean Diet (MD) with a shift toward a Western diet. This study aims to understand the reasons behind moving away from the MD among children, by providing an overview of the different correlates influencing MD adherence among preschool and school-age children (3–8 years old).</p> Methods <p>A systematic review was conducted and reported in accordance with the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines and registered in the Prospero database (CRD42023370607). Literature was searched in PubMed, Web of Science and PsycINFO databases for studies, without restrictions on publication date. Inclusion criteria were preschool and school-aged children, studies conducted in Mediterranean countries, and statistical analyses of the association between the different correlates and MD adherence quantified by a validated dietary assessment. Studies that did not provide sub-analyses for the specified age group were excluded. A quality analysis of the included studies was performed using the National Collaborating Centre for Methods and Tools (NCCMT) scale.</p> Results <p>A total of 12 studies were included, primarily from European Mediterranean countries, with fewer studies from the Middle East and North Africa. The vast majority of the included studies reported on interpersonal correlates related to the parent’s influence on MD adherence, while child’s age and sex, physical activity, and time spent on video games were classified as individual, and only the place of residence was classified as an environmental correlate. The quality assessment generally showed weak scores.</p> Conclusion <p>The primary factors influencing MD were interpersonal correlates related to parents, indicating that interventions should target both children and parents to effectively reinforce MD adherence.</p>