The present invention provides a hydrogen storage system for a vehicle which is readily attachable to and detachable from the vehicle. The hydrogen storage system includes a plurality of hydrogen tanks filled with hydrogen at the outside and is mounted on the top of a rear underfloor of the vehicle in the form of a cartridge. For this purpose, the present invention provides a hydrogen storage system for a vehicle, including a hydrogen storage housing, accommodating a hydrogen storage material filled with hydrogen at the outside and easily attached to and detached from the vehicle using a quick connector.