Provided is a pressure-sensitive adhesive (PSA) sheet including a PSA layer formed from a PSA composition including a base polymer, crosslinking agents of two or more species having mutually different types of crosslinkable functional groups, and an azole-based rust inhibitor. Here, one of the crosslinking agents of two or more species is an isocyanate-based crosslinking agent. Monomeric components constituting the base polymer include a carboxy group-containing monomer. The amount of the azole-based rust inhibitor in the PSA layer is less than 8 parts by weight with respect to 100 parts by weight of the base polymer.