A chain block including: a gear unit including a pinion gear, and a load gear configured to rotate integrally with a load sheave member; a case body configured to house the gear unit and to be supplied with grease being semifluid or semisolid at a working temperature as a lubricant and a built-in cover arranged inside the case body, wherein: the built-in cover includes a first peripheral wall part configured to cover an outer peripheral side of the pinion gear, and a second peripheral wall part provided to be larger in diameter than the first peripheral wall part, the first driven gear body including a first large-diameter driven gear meshing with the pinion gear; and the built-in cover is provided in a circulation shape without a break by continuation of the first peripheral wall part and the second peripheral wall part.