A water-absorbent sheet comprising a structure in which an absorbent layer containing a water-absorbent resin and an adhesive is sandwiched with a hydrophilic nonwoven fabric, wherein the water-absorbent sheet has a structure in which the absorbent layer is fractionated into a primary absorbent layer and a secondary absorbent layer with a substrate layer formed by laminating two or more layers of a substrate having breathability adhered together with an adhesive, wherein the substrate layer satisfies the following requirements (1) and (2): (1) the substrate layer having a basis weight of 25 g/m 2 or more; and (2) the substrates having breathability being adhered therebetween with an adhesive in an amount of from 0.1 to 50 g/m 2 . The water-absorbent sheet of the present invention exhibits some excellent effects that the water-absorbent sheet is capable of accomplishing thinning and avoidance of gel blocking phenomenon and liquid leakage, while obtaining basic properties as a water-absorbent sheet at a high level, even for a water-absorbent sheet containing a very small amount of pulps.