OBJECTIVES: The aim of the current study was to examine the influence of socioeconomic status (SES) on physiological (lipid profile, obesity indices) and behavioral (dietary habits, physical activity) cardiovascular disease (CVD) risk factors among primary schoolchildren in Istanbul. DESIGN: Cross sectional study. SETTING: One private school and two public schools from different SES districts in Istanbul. PARTICIPANTS: 510 randomly selected children aged 12 and 13 years old (257 boys, 253 girls). RESULTS: The prevalence of overweight (15.2%) and the energy intake (p < 0.001 and p < 0.05 for boys and girls respectively) were found to be higher for the middle/high SES group for both genders. Regarding biochemical indices, middle/high SES children had higher values of High Density Lipoprotein-cholesterol (HDL-C) (p < 0.001 and p < 0.05 for boys and girls respectively) and lower values of TC/HDL-C ratio and LDL-C/HDL-C ratio (p < 0.05 and p < 0.001 for boys and girls respectively). This could be attributed to the higher physical activity levels observed for middle/ high SES children (p < 0.001). CONCLUSION: The findings of the current study revealed a coexistence of both overweight and higher energy intake in middle/high SES children, as well as a coexistence of underweight and lower physical activity levels in low SES children. These observations should guide the public health policy in developing appropriate intervention strategies to efficiently tackle these health and social issues early in life.