A man diagnosed with alcoholic liver cirrhosis complained of abdominal distention due to massive ascites. The ascites did not resolve with diuretic agents. The serum-ascites albumin gradient value of 1.9 g/dL and the total protein level in the ascites of 3.1 g/dL indicated the ascites to have been caused by portal hypertension. Hypothyroidism was detected, and the patient received supplementation with levothyroxine. The ascites dramatically decreased after supplementation with levothyroxine. We herein conclude that the ascites in the present case had thus been strongly influenced by portal hypertension, which was induced by liver dysfunction associated with liver cirrhosis and hypothyroidism.