PURPOSE: To obtain the titled unit having high hydrogen occulusion and release efficiencies due to a large amount of metallic hydride particles by settling and depositing the solid matter in an aqueous slurry contg. inorg. particles and org. short fibers, dehydrating and drying the resulting deposit and baking it.

CONSTITUTION: Inorg. particles of 0.1W0.3mm particle size such as alumina particles and org. short fibers of 2W3mm length such as refined linter pulp are dispersed in water in 1/1W1/5 volume ratio to prepared an aqueous slurry. This slurry is fed to a vessel whose bottom is microporous and the solid matter in the slurry is settled and deposited. The resulting deposit is dehydrated by suction from the bottom, dried and baked to obtain a hydrogen occlusion unit made of a porous formed body having satisfactory strength and high porosity.