Myxedema ascites caused by hypothyroidism is rare, so its diagnosis is often delayed and patients frequently receive unnecessary procedures such as liver biopsies and exploratory laparotomies. We report a 71-yr-old man with clinical ascites that was the first manifestation of hypothyroidism, and which resolved completely in response to thyroid hormone replacement therapy. To our knowledge, this is the first report of myxedema ascites in Korea. A review of the literature revealed 51 well-documented cases of myxedema ascites. Analyses of ascites from patients in this condition usually show high protein (>2.5 g/dL) and low white blood cell counts, with a high proportion of lymphocytes. A consistent feature is the good response to thyroid hormone replacement therapy, which has always led to resolution of the ascites. Myxedema ascites is thus rare but easy to treat; it should be borne in mind, especially if the ascites fluid has a high protein content.