Rubber composition for run-flat tire and run-flat tire comprising the same

The present invention provides a rubber composition for a run-flat tire which can have compatibility of low heat build-up with a high degree of hardness and improve durability of the run-flat tire, and the run-flat tire comprising the same. The present invention relates to a rubber composition for a run-flat tire containing 10 to 100 parts by weight of carbon black and at least 3 parts by weight of a compound satisfying the formula represented in the following: - ( R - S x ) n - (wherein R is (CH-CH-O)-CH-CH, x is an integer of 3 to 6, n is an integer of 10 to 400 and m is an integer of 2 to 5) based on 100 parts by weight of a rubber composition, and the run-flat tire having a reinforcing layer comprising the same.