PURPOSE: To obtain a cement composition having high forming stability and high water retaining property together by kneading a cement with water and an emulsified copolymer containing an α,β-monoethylenic unsaturated carboxylic acid.

CONSTITUTION: When a cement is blended and kneaded with water and a high polymer compound or a cement is blended and kneaded with water, an aggregate and a high polymer compound to provide the aimed cement composition, the blending and kneading is carried out as follows: An emulsified copolymer containing an α,β-monoethylenic unsaturated carboxylic acid as a monomer is used as the above-mentioned high polymer compound. In the above-mentioned emulsified copolymer, especially a monomer having at least two α,β-ethylenic unsaturated double bonds in the molecule works as crosslinking ingredient, increases molecular weight of the emulsified copolymer itself and forms three- dimensional structure and moreover improves viscous property and water retaining property. Methacrylic acid is especially preferably used as an α,β- monoethylenic unsaturated carboxylic acid.