The present invention intends to provide a pressure-sensitive adhesive sheet for dicing which inhibits the generation of fibrous scraps and has good expandability. The present invention relates to a pressure-sensitive adhesive sheet for dicing, which includes a base material and at least one pressure-sensitive adhesive layer disposed on at least one surface the base material, in which the base material contains a polymer having a random copolymer block, and the random copolymer block contains a block (I) containing, as a main constitutional unit, a constitutional unit represented by the following structural formula (A): --(CH.sub.2--CH.sub.2--CH.sub.2--CH.sub.2)-- (A) and a block (II) containing, as a main constitutional unit, a constitutional unit represented by the following structural formula (B): ##STR1##