This study was conducted to evaluate nutritional status of school children by biochemical assessment method. Subjects were 308 school children from 4th to 6th grade living in Bucheon city. Their blood glucose, total protein, albumin, total cholesterol, and triglyceride (TG) concentrations were determined. Mean blood glucose concentration was 77.56 mg/dl and $81.2\%$ of children had normal blood glucose concentration. The average proportion of hypoglycemia was $18.8\%$ among the three grades and prevalence of hypoglycemia in 4th grade school children was highest ($21.8\%$). Mean serum total protein and albumin levels were 7.14g/dl and 4.35g/dl, respectively, and all the subjects except only one were in normal range of total protein and albumin. Mean serum TG and total cholesterol concentrations were 145.82mg/dl and 94.50mg/dl. Serum TG and total cholesterol levels showed same pattern that the concentrations decreased in proportion to grade. Especially, there was significant difference between grades in serum total cholesterol. Furthermore, $11.7\%$ of 4th, $6.8\%$ of 5th, and $2.8\%$ of 6th grade school children have borderline hypertriglycemia or hypertriglycemia, risk factors of obesity or cardiovascular disease later in life. Taken together, there was conflict phenomenon that undernutrition of hypertriglycemia and overnutrition of hypertriglycemia existed together. Therefore, it is needed to develop discriminating and personalized nutritional feeding, counseling, and education program to cover the children of under- or over- nutritional status.