The water droplet generating system includes a vessel, an opening/closing valve, a moisture absorbent member, and a condenser portion. The vessel has an opening portion. The opening/closing valve opens and closes the opening portion. The water absorbent member absorbs and releases water vapor depending on a change of humidity. The condenser portion is communicated with the inside of the vessel and cools water vapor released from the moisture absorbent member to be at a dew point of water vapor or less. When the opening portion is opened, the moisture absorbent member absorbs water vapor in atmosphere. When the opening portion is closed, the moisture absorbent member releases water vapor, and the condenser portion condenses water vapor, which is released from the moisture absorbent member, to generate a water droplet.