The invention refers to a fibrous sheet having a basis weight of between 20 and 1000 g/m 2 that disintegrates in water, comprising 10% to 70% starch on the basis of the total weight of the dry fibrous sheet, the disintegration time in water, measured in accordance with the NF Q34-020 standard applied to a specimen of the sheet of 9 x 8 cm 2 , is less than 50 seconds, preferably less than 35 seconds, and more particularly less than 15 seconds, of which the loss of strength measured in accordance with the table test as reported in the specification corresponds to the loss of strength of a specimen of said sheet forming an angle of at least 85°, preferably between 88° and 90°, after having being wetted with water for a duration of 6 seconds and/or the residual wet strength of which relative to its dry strength, as measured according to the ring crush test described in the specification, is less than 1%. The fibrous sheet of the invention is used for instance for the manufacture of a water disintegrable core in a roll of tissue paper.
