An automatic urine disposal device has a urine collecting pad, vacuum pump, and urine tank. In the urine collecting pad, the top sheet comes in contact with the wearer's skin, the hydrophilic sheet is disposed on the bottom of the top sheet, and the urine absorbent sheet is disposed at the bottom. When discharged urine flows in the top sheet, the hydrophilic sheet widely diffuses urine to saturate its entire surface and then becomes non-breathable. As the vacuum pump vacuums the air from the urine tank, urine is directed from a urine drainage port of the urine collecting pad via a urine drainage tube to the urine tank which is a sealed container.