PROBLEM TO BE SOLVED: To provide a roll for melting extrusion molding size enlargement which can attempt transcriptional improvement sufficiently.SOLUTION: A roll for melting extrusion molding size enlargement 1A used in melting extrusion molding of thermoplastic resin consists of: a metal roll body unit 10 provided with a heat medium duct 11 inside; a first tubular member 12 covering the surface of the central part of the roll body unit 10; and a second tubular member 13 covering the surface of both ends of the roll body unit 10. The first tubular member 12 is produced with a first metallic material having a heat conductivity not less than 40 W/mK. The second tubular member 13 is produced with a second metallic material having a heat conductivity not more than 20 W/mK. The first tubular member 12 and the second tubular member 13 are joined with at least one part.
