Disclosed herein are a humidifying apparatus which may be prevented from being contaminated. A humidifying apparatus comprises a water tank configured to store water, a filter assembly configured to filter the water stored in the water tank and a humidifying assembly configured to perform humidification by absorbing and vaporizing the water filtered by the filter assembly, a drain flow passage provided at a lower surface of the humidifying assembly, wherein residual water remaining after being absorbed in the humidifying assembly is recovered in the water tank via the drain flow passage, and a guide rib configured to guide the water recovered in the water tank is provided in the water tank.