Abstract: A seabed-resource lifting device causing deep-sea mud that contains rare-earth elements to rise from depths of 5000 m or more. This seabed-resource lifting device includes: a transport hose that includes a first hose and a second hose and that hangs from a resource-recovery vessel to the seabed; a crawler-type collector that includes a first suction chamber that sends mud from the seabed to the first hose, and a second suction chamber that sends mud from the seabed to the second hose; a water electrolyzer that, using electricity supplied from the resource-recovery vessel, electrolyzes water so as to generate hydrogen gas and oxygen gas; and a gas-injection device that injects the generated hydrogen gas and oxygen gas into the first suction chamber and the second suction chamber, respectively. Mud that contains rare-earth elements rises with sea water due to the buoyancy of the hydrogen gas or oxygen gas.