A refrigerant supply device with a small lateral width and a capacity to supply refrigerant evenly among heat receivers disposed in multiple tiers needs to be provided.A refrigerant supply device for distributing, by force of gravity, liquid phase refrigerant to heat receivers disposed in a plurality of tiers includes: a first conduit for supplying the refrigerant to the heat receivers; a second conduit provided in parallel with the first conduit; a first aperture provided in the first conduit for supplying the refrigerant to one of the heat receivers; a first blocking means provided below the first aperture for blocking the first conduit; a first communication opening provided above the first aperture and communicating the first conduit and the second conduit; a second communication opening provided below the first blocking means and communicating the first conduit and the second conduit; and a second blocking means provided below the second communication opening for blocking the second conduit.