Childhood obesity is an urgent public health problem with extensive implications. Notably, it often persists into adulthood, increasing the risk of chronic non-communicable diseases, straining the healthcare system, and reducing quality of life. Acknowledging this concern, the primary aim of this study was to explore the potential relationship between serum lipid concentrations and anthropometric parameters in obese children and adolescents, particularly in the context of their adherence to the Mediterranean diet. The research was conducted at the Split Clinical Hospital Center, specifically in the polyclinic for children's diseases, within the diabetes and endocrinology clinics, from March to July 2023. It included a questionnaire, anthropometric measurements, and biochemical parameters. A total of 32 participants were involved in the study. The collected data were then subjected to statistical analysis. Children from the Split-Dalmatia County participated in the research, with 20 (63 %) male and 12 (38 %) female respondents. The median age of the participants was 13 years, with ages ranging from 8 to 18 years. The majority were overweight (62.5 %), while the rest were obese (37.5 %). Results from the KIDMED questionnaire indicated that over half of the participants (69 %) had a very low-quality diet according to Mediterranean diet (MeDi) standards, and 31 % required dietary adjustments to improve their adherence to MeDi principles. The association assessment shows that the KIDMED index is proportional to the BMI percentile, although no significant associations were found with other anthropometric parameters or lipid status. Participants needing adjustments to MeDi had significantly higher BMI percentiles (Mann-Whitney U test, P = 0.03), but no significant differences were noted in other anthropometric parameters or lipid status according to the KIDMED index. Furthermore, no significant association was found between serum LDL and triglyceride values and anthropometric parameters. However, HDL values were inversely proportional to body mass (Rho = -0.401). This research demonstrated a connection between excess body weight, obesity, and low-quality nutrition according to MeDi principles. Considering the positive effects of the Mediterranean diet on overall health, it is crucial to educate children and parents in the Split-Dalmatia County on adopting proper eating habits and lifestyles aligned with the Mediterranean diet and culture.