Mucorrhea was first noticed by a woman patient at the age of 39; in the ensuing 10 years it worsened until there were occasional discharges of mucus from the rectum during sleep. At the age of 50, serious electrolyte imbalance was manifested by neuromuscular symptoms including convulsions and coma, and the diagnosis of villous adenoma was made. The soft tumor, its surface covered with villous projections, was actively secreting mucus and completely lined the rectum. The affected segment of intestine was removed surgically, a temporary colostomy was made, and an anastomosis was established between the sigmoid colon and the anal canal. No signs of malignancy werefound. The colostomy was closed two months later, and the patient recovered normal gastrointestinal function as well as normal electrolyte balance.