A defecation/urination determination apparatus including: a feces/urine receiving member that is placed to face a body of a wearer and receives discharged feces and urine a temperature sensor that is placed in the feces/urine receiving member and a control section that determines by a signal that is output from the temperature sensor whether at least one of urine and feces has been discharged, based on a rate at which a temperature falls after detection of a rise of the temperature.