A liquid remaining amount detecting mechanism includes a rotating member that is disposed in a storage chamber of a tank that stores a liquid, and a sensor. The rotating member is rotatable about a shaft and includes a float that receives buoyancy from the liquid, a detection target portion that is detectable by the sensor, and a through-hole into which the shaft is inserted. The sensor is disposed at a position facing a portion of a locus of the detection target portion when the rotating member is rotated. The liquid remaining amount detecting mechanism further includes a liquid pool portion, at least a portion of which is located between an outer peripheral surface of the shaft and an inner peripheral surface of the through-hole to hold the liquid.