An excretion detection device comprises: electrode unit configured by using materials with different ionization tendencies； a neutralizer retention unit configured to retain a neutralizer for reducing the hydrogen ion index of the bodily waste； and an active tag configured to notify the excretion from the living body to outside the excretion detection device. The electrode unite is provided at a position where the electrode unit can be in contact with the bodily waste. The neutralizer retention unit is provided at a position where the neutralizer can be in contact with the bodily waste.
