Cancer is a leading cause of mortality in children and results in a significant disease burden. Lipid metabolic reprogramming emerges as a pivotal cancer hallmark, bearing profound implications for understanding tumorigenesis, developing treatment strategies, and improving prognoses. However, research on lipid metabolism and lipid nutritional interventions related to childhood cancers is notably limited compared to adult cancers. This review focused on the current understanding of fatty acid, cholesterol, and phospholipid metabolism in childhood cancers and discussed the correlation between major lipid dietary patterns (such as high-fat, ketogenic, and Mediterranean diets) and the development and progression of childhood cancers. This review also highlighted existing research gaps on the mechanisms of lipid metabolism and the effects of major lipid dietary patterns, and warranted improved research depth, experimental design, and sample size. Therefore, we advocate for future epidemiological, basic science, and multidisciplinary research in the field of childhood cancers to understand more comprehensively and profoundly the role of lipid nutrition in the prevention and treatment of pediatric cancers.