Cationic additives are generally used in coated inkjet printing paper to improve water fastness. This study develops a coating for photographic inkjet printing paper that achieves good water fastness without cationic additives. Porous ?- Al 2 O 3 flake powder, which has high porosity, high specific surface area, and positive surface charges, is used as a pigment in the coating. The water fastness of prints is evaluated using an immersion method combined with the measurement of light absorbance of the water used for immersion. The results indicate that water fastness can be improved by introducing ?- Al 2 O 3 powder into the coating pigments. The intrinsic crevices and pores of ?- Al 2 O 3 provide concave sites for dye colorants and enhance the sorbtion of liquid phase of inks, but stick the dye colorants on the pigment surface. Furthermore, the positive surface charge of ?- Al 2 O 3 provides cationic sites for the fixation of dye on the coating surface via electrostatic interactions.