The present invention provides a rubber composition having superior moldability, wear resistance, and grip performance, and tires therewith. The present invention relates to a rubber composition comprising: a copolymer (B) constituted of a vinyl alcohol polymer (B-1) region and a diene polymer (B-2) region; and a rubber component (C), wherein the rubber composition comprises 1 to 20 parts by mass of the copolymer (B) relative to 100 parts by mass of the rubber component (C).