Abstract: A curable water-swelling water stop material including: 100 parts by mass of a resin component which includes 40 to 100 parts by mass of a curable resin having a hydrolysable alkoxysilyl group and 0 to 60 parts by mass of a polyether polyol; 0.3 to 25 parts by mass of an aminosilane coupling agent; 20 to 250 parts by mass of a water-absorbent resin; and 0 to 160 parts by mass of an extender pigment, in which the hydrolysable alkoxysilyl group having a structure represented by Formula (1) —X—CH2—SiR1Y(OR2)3-Y, in which X is a bonding functional group having a heteroatom with an unshared electron pair and bonding to a methylene group bonding to a silicon atom of a hydrolysable silicon group, R1 and R2 are C1-C3 alkyl groups respectively, and Y is 0, 1 or 2.