Edge separation in a turned-up end portion (5E) of a carcass ply (5) is suppressed. In a pneumatic tire comprising a bead core (4) embedded in a bead portion (3) and a carcass ply (5) turned up and locked around the bead core (4), a rubber sheet (10) is prepared using a wet masterbatch containing natural rubber and/or polyisoprene rubber and carbon black, and the rubber sheet (10) is arranged on at least one of front and back sides of the turned-up end portion (5E) of the carcass ply (5).