A coating paper which can be removed by water comprising a substrate paper of single layer or lamellar structure having two or more layers which has at least one water decaying layer containing 5-100 wt % of water insoluble fibrous carboxy alkyl cellulose and a water base color is coated on said substrate paper, wherein a coating layer and at least a part of substrate paper which is a supporter of said coating layer has a characteristic of easily removing, dispersion and dissolving by contact with water, and can provide a water decaying coating paper used preferably for an use of label for a returnable container which may easily remove by contact with water and excellent in printing aptitude and a method for preparation thereof can be provided.