The present disclosure provides a water disintegratable leak-proof sheet for an absorbent article that has an excellent leak-proof property during wear and excellent water disintegrating property after disposal. The water disintegratable leak-proof sheet of the present disclosure has the following construction. A water disintegratable leak-proof sheet for an absorbent article comprising a water disintegratable base material layer and a water-insoluble and biodegradable resin layer on the water disintegratable base material layer, wherein the tearing strength in the planar direction of the water disintegratable leak-proof sheet is no greater than 0.15 N/40 mm in both a first direction and a second direction perpendicular to the first direction.