This study was conducted to compare the serum composition and urinary excretion in four institutional groups and the effects of intakes of good foods and harmful foods according to the Sasang constitiution for a short time on serum and ruine compositon. The contitutions of 33 female stucdents were classified by O-ring test and muscular strength test according to the Sasang constitution, The number of each institutional group was So-yang-in 11, So-em-in 10 and Tae-em-in 12. No subject belonged to Tae-yang-in There were no significant differences among contitutional groups in the values of most serum composition and urinary excretion Serum levels of total cholesterol, glucose, calcium and phosphorus in Tae-em-in was the highest among groups and the level of albumin and total protein in So-em-in was highest. The values of serum compositions changed after the 33 subjects took good foods and then harmful foods according to The Sasang constitution for a short time(5 days). Dietary behavior of the subjects had some effects among the constitutional groups in the values of most serum composition and urinary excretion. But the effects of dietary behavior on the serum composition and urinary excretion showed various trends in the four institutional groups.