Abstract: A vacuum toilet system comprises a toilet bowl having a cover mounted for movement relative to the toilet bowl between an open position and a closed position, the cover being in at least partially sealing relation with the rim when in the closed position. A liquid supply opening is provided for introducing liquid into the toilet bowl when the cover is in the closed position. A discharge valve connects the outlet opening of the toilet bowl to a sewer pipe, in which a partial vacuum can be established. A reservoir has an inlet opening for receiving rinse liquid and an outlet opening in communication with the liquid supply opening. The inlet opening of the reservoir is exposed to substantially the same pressure as the liquid supply opening when the toilet bowl cover is in the open position and the discharge valve is closed. Rinse liquid is drawn from the reservoir into the toilet bowl by way of the liquid supply opening when the discharge valve is open and the cover is in the closed position.