A recent study reported that coronary artery calcification (CAC) and serum homocysteine were well associated; however, no report is available for the cut-off value of serum homocysteine according to increase of coronary-artery calcification volume score (CVS). The data of 469 out of 777 subjects in 1 health promotion center located in Seoul were selected after exclusion of the missing data of serum homocysteine and CVS. CVS was categorized into 2 groups: CVS=0 and CVS>0. Serum homocysteine according to the CVS groups was compared, and the cut-off value of serum homocysteine according to the increase of CVS (>0) was calculated using the receiver operating characteristic curve. Mean age was 54.5 years and the proportion of females was 22.2%. Mean serum homocysteine concentration and CVS were 11.2 μmol/L and 50.4, respectively. After adjustments for age and sex, serum homocysteine was associated with CVS (r=0.167, p=0.001), and Log(Homocysteine) also showed a significant difference according to the CVS groups. The cut-off value of serum homocysteine according to the increase of CVS (>0) was 9.45 μmol/L (area under the curve=0.569 (95% CI 0.512 to 0.625), p=0.015). The cut-off value of serum homocysteine was 9.45 μmol/L according to the increase of coronary-artery CVS.