Objectives: To evaluate the effects of the miso soup containing soy protein hydrolyzate with bound phospholipids (c-SPHP) on the serum cholesterol levels in hypercholesterolemic subjects in a randomized double-blind study was carried out over a three-month period. Methods: Subjects were Japanese adult male volunteers whose serum total cholesterol levels were between 200-280mg/dL. The subjects were divided into two groups randomly. Each test diet was orally administered in a miso soup form that contained c-SPHP or casein hydrolyzate (placebo). The subjects were given one test diet daily (c-SPHP 3g/day). The study consisted of a two-week pre-feeding period, a three-month feeding period, followed by a two-week post-feeding period. Results: After three months of miso soup ingestion, serum total cholesterol of c-SPHP-miso soup group (n = 11) decreased significantly compared with the placebo group (n = 11) (p < 0.05) and from the initial level (7.6%, p < 0.01). LDL-cholesterol tended to be lower level compared with the placebo group. There was not a significant difference in HDL-cholesterol level throughout the study. Conclusions: This study suggests that miso soup, containing c-SPHP, has also remarkable improving effects similar to c-SPHP on the serum cholesterol levels in hypercholesterolemic subjects.