A rubber composition includes a chloroprene-based rubber, 5 to 80 parts by mass of silica, 0.5 to 15 parts by mass a silane coupling agent, and 0.5 to less than 20 parts by mass of a hydrate. The rubber composition satisfies at least one of (i) and (ii): (i) the rubber composition includes 0.1 to 3.0 parts by mass of 3-methyl-thiazolidine-2-thione; (ii) the rubber composition includes 0.1 to 3.0 parts by mass of compound A that is at least one of a thiourea-based compound, 3-methyl-thiazolidine-2-thione, and di(5-mercapto-1,3,4-thiadiazol-2-yl) disulfide; and 0.01 to 3.0 parts by mass of compound B that is at least one of a thiuram-based compound, a sulfenamide-based compound, a thiazole-based compound, a guanidine-based compound, a benzimidazole-based compound, N-phenyl-N-(trichloromethylthio)benzenesulfonamide, and a diazabicycloundecene-based compound.