Childhood obesity is a major public health problem. It has a direct impact on the quality of life of children and adolescents, as well as on their future risk of developing chronic diseases. Dietary patterns rich in fats and sugars and lacking dietary fibers, vitamins, and minerals, as well as lack of physical exercise have been associated with the rise of obesity prevalence. However, factors that contribute to the preference for foods rich in these nutrients are not well established. Taste is recognized as an important predictor of food choices, and polymorphisms in taste-related genes may explain the variability of taste preference and food intake. The aim of this research is to evaluate the influence of polymorphisms of the sweet taste receptor gene on diet and metabolic profile in obese children and adolescents. A cross-sectional study with 513 obese children and adolescents and 135 normal-weight children was carried out. A molecular study was performed for the single nucleotide polymorphisms (SNPs) rs9701796 and rs35874116 of , and dietary intake, anthropometric parameters (weight, height, waist circumference, waist-to-height ratio (WHtR)), and metabolic profile (including fasting glucose, insulin, triglyceride, high-density lipoprotein (HDL)-cholesterol, and leptin levels) were analyzed. The variant rs9701796 was associated with increased waist-height ratio, as well as with a higher chocolate powder intake in obese children. The variant rs35874116 was associated with a lower dietary fiber intake. In conclusion, there was no relationship between genotypes and risk of obesity. Obese adolescents carrying the serine allele of SNP rs9701796 in TAS1R2 showed higher waist-to-height ratio and chocolate powder intake, whereas those carrying the valine allele of SNP rs35874116 in TAS1R2 were characterized by lower dietary fiber intake.