BACKGROUND: Approximately 10% of all colorectal adenomas are constituted by villous adenomas. Their relationship with hydroelectrolytic depletion is rare. We report two cases with villous adenoma that presented hydroelectrolytic depletion with clinical and surgical management, exclusively. CLINICAL CASES: Case 1. Patient was a 76-year-old female with hypertension and 3 months evolution of symptoms such as asthenia, adynamia, unexplained weight loss, and abundant mucus with diarrhea. Serum potassium value was 2.2 mEq/l . Upon rectal exam we found a sessile, exophitic soft tumor with irregular surface of approximately 10 cm in diameter. We also performed a transanal resection of tumor reporting villous adenoma. The patient was discharged from the hospital at the 4th postoperative day with potassium values within normal limits. Case report 2. Patient was a 76-year-old female with diabetes and hypertension of long evolution. She reported a 4-month clinical evolution with non-bloody diarrhea and abundant mucus. She reported nausea, vomiting and no unexplained weight loss. Serum potassium value was 2.1 mEq/l . During the rectal exam we identified a sessile, polypoid, 5-cm diameter tumor that did not involve deep planes. In addition, we carried out a transanal resection of the polyp. The patient was discharged from the hospital on the 5th postoperative day. Potassium value was 4.3 mEq/l. CONCLUSIONS: Size and location of the villous adenoma are related to the production of mucus secretory diarrhea. The inhibiting well-known indomethacin of the prostaglandins has been used to decrease the mucus secretion. In every patient with presence of mucus, persistent diarrhea and occasional rectal bleeding of 1 month, it is necessary to carry out lower endoscopy to rule out the presence of villous adenoma.