It is to provide a rubber composition for hot air cross-linking excellent in stability of storage and capable of cross-linking under the presence of ais, and to provide a cross-linked rubber having excellent mechanical property and heat resistance of the rubber after the cross-linking.
A rubber composition for hot air cross-linking comprises 100 parts by mass of one or more rubber components (A) selected from the group consisting of an ethylene-propylene rubber and an ethylene-propylene-diene rubber, 1.0 parts by mass or more and 15.0 parts by mass or less of an organic peroxide (B), and 0.01 parts by mass or more and 9.0 parts by mass or less of a reducing agent (C).