Objective: Hypertension can develop during childhood and adolescence, posing long-term risks for cardiovascular disease and premature mortality. This study aims to examine the relationship between genetic factors, as indicated by parental blood pressure, and children’s socioeconomic status and lifestyle habits, with a focus on their relationship to children’s blood pressure. Design and method: The Korea National Health and Nutrition Examination Survey (KNHANES) is a nationally representative health survey conducted in South Korea. From 2020 to 2022, blood pressure (BP) was measured using a manual auscultatory device (Greenlight 300) following the standard KNHANES protocol. Data from 1,931 children aged 6 to 18 years, with linked parental information, were included in the analysis. Household income, parental education levels, children’s lifestyle habits, and cardiometabolic factors were examined. Correlation analysis and multiple regression analysis were employed to explore these relationships. Results: The systolic BP (SBP) and diastolic BP (DBP) of children showed correlation coefficients of 0.21/0.18 and 0.21/0.19, respectively, with the SBP and DBP of mothers and fathers. When at least one parent had been diagnosed with hypertension, children’s SBP was 2.66 mmHg higher (P < 0.0001, t-test), and their DBP was 3.10 mmHg higher (P < 0.0001, t-test). In a multiple regression analysis across all age groups, age and sex of children showed a significant negative association with blood pressure, while children’s weight and parental blood pressure demonstrated a significant positive association. Although maternal education level showed a negative coefficient in the overall analysis, it was not statistically significant. However, a moderating effect was observed when stratified by age group, with a regression coefficient of -0.93 (P = 0.1068) in the 6–12 age group and -1.33 (P = 0.0382) in the 13–18 age group. Conclusions: Parental BP shows relatively stronger correlation with children’s BP compared to other factors. However, understanding the moderating effects of socioeconomic factors, such as parental education, is essential for developing effective intervention strategies to manage children’s BP and reduce long-term cardiovascular risks.