Disclosed is a composition for the regeneration of a cartilage or the treatment of a cartilage disease, which comprises, as an active ingredient, a univalent metal salt of alginic acid having a reduced endotoxin level to such a extent as not to induce an inflammation or attack of fever substantially. It becomes possible to provide: a composition for the regeneration of a cartilage, which is improved in cartilage-regenerating activity and applicability to a cartilage-damaged area； and a composition for the treatment of a cartilage disease, which has all of an effect of protecting a cartilage from a mechanical stimulus, an effect of preventing the deformation of a cartilage by wear or inflammation, an effect of repairing a cartilage-damaged part, and an effect of preventing an inflammation or pain in a joint tissue.
