To readily obtain the subject substance not using a plasticizer, an adhesive, etc., simply being wetted with water, molded and dried, excellent in disintegration with water, rapidly being broken down into a fibrous state, effective for maintaining the sense of beauty of an environment, useful as a tobacco filter, etc.

At least a part of the surface of a cellulose substance is hydrolyzed until bond strength is mutually developed by wetting the hydrolyzed cellulose substance with water, molding and drying. The substance is powder or a fiber. Cellulose acetate powder having 2.54 acetyl substitution degree, 280 polymerization degree and about 220μm average particle diameter, etc., are used. The hydrolysis treatment is preferably carried out with an alkali (e.g. sodium hydroxide, etc.) or an acid (e.g. hydrochloric acid).