OBJECTIVE The purpose of this study is to examine the association of plasma Hcy, folate and vitamin B(12) levels on CVD risk factors among children in Taiwan. METHODS After multistage sampling, we selected randomly 1,235 children (609 boys and 626 girls) aged 12 to 15 yr. Plasma Hcy levels was measured using ABBOTT Imx analyzer, while plasma folate and vitamin B(12) were measured using ACS: 180 automated chemiluminescence analyzer. Anthropometric, blood pressure (BP) and other biochemical CVD risk factors including serum total cholesterol (CHOL), triglyceride (TG), high density lipoprotein-cholesterol (HDL-C), apolipoprotein A1 (apoA1) and B (apoB) and lipoprotein(a) [Lp(a)]were measured using standard methods. We also calculated low density lipoprotein-cholesterol (LDL-C) and TCHR (total cholesterol to HDL-C ratio) as atherogenic indices. RESULTS Boys were taller and heavier, having higher body mass index (BMI), systolic blood pressure (SBP) and plasma glucose levels but lower diastolic blood pressure (DBP), heart rate (HR), cholesterol, TG, HDL-C, LDL-C, TCHR, and Lp(a) levels than girls. Boys also had higher plasma Hcy and lower folate, vitamin B(12), levels than girls (for plasma Hcy, mean +/- SD, 10.50 +/- 4.13 vs. 8.95 +/- 2.61 micromol/L for boys vs. girls, respectively). Plasma Hcy levels were significantly correlated positively with body height, body weight, SBP and DBP in both genders. Body height, body weight, BMI and SBP levels were found to increase with trend among different quintile plasma Hcy subgroups on boys but not on girls. Plasma folate and vitamin B(12) were decreased significantly along with the higher quintile plasma Hcy subgroup in both genders. CONCLUSIONS Boys had higher plasma Hcy levels than girls after adjusting for age. Furthermore, plasma Hcy levels were significantly associated with anthropometric parameters, such as body height and weight and blood pressure, but not related with lipid profiles among children in Taiwan.