A composite roll for rolling having a structure comprising centrifugally cast outer and intermediate layers (1, 2) both made of an Fe-based alloy, and an inner layer of ductile cast iron, said layers being integrally fused to each other; characterized in that said outer layer has a composition comprising by mass 1-3% of C, 0.3-3% of Si, 0.1-3% of Mn, 0.5-5% of Ni, 1-7% of Cr, 2.2-8% of Mo, 4-7% of V, 0.005-0.15% of N, and 0.05-0.2% of B, wherein said outer layer optionally further contains: 0.1% to 3% by mass of Nb and/or 0.1% to 5% by mass of W, and/or at least one selected from the group consisting of: 0.1% to 10% by mass of Co, 0.01% to 0.5% by mass of Zr, 0.005% to 0.5% by mass of Ti, 0.001% to 0.5% by mass of Al, and 0.3% or less of S, the balance being Fe and inevitable impurities such as P, Cu, Sb, Te and Ce, wherein the P content is 0.1% or less by mass, and the total amount of the inevitable impurities is 0.7% or less by mass; said intermediate layer contains 0.025-0.15% by mass of B; the B content in said intermediate layer is 40% to 80% of the B content in said outer layer; and the total amount of carbide-forming elements in said intermediate layer is 40-90% of the total amount of carbide-forming elements in said outer layer, wherein the carbide-forming elements in said outer and intermediate layers (1, 2) are Cr, Mo, V, Nb and W, wherein the B content in the intermediate layer is determined as the concentration of B at a midpoint, Am, between inflection points, A1, A2, in a graph in which the concentration of B measured by inductively coupled plasma optical emission spectroscopy is plotted against the depth from the roll surface, wherein the inflection points, A1, A2, are the boundary regions between the outer layer and the intermediate layer, and between the intermediate layer and the inner layer, respectively, and wherein the total amount of carbide-forming elements in said intermediate layer is the total concentration of each carbide-forming element measured at the midpoint, Am. characterized in that said outer layer has a composition comprising by mass 1-3% of C, 0.3-3% of Si, 0.1-3% of Mn, 0.5-5% of Ni, 1-7% of Cr, 2.2-8% of Mo, 4-7% of V, 0.005-0.15% of N, and 0.05-0.2% of B, wherein said outer layer optionally further contains: 0.1% to 3% by mass of Nb and/or 0.1% to 5% by mass of W, and/or at least one selected from the group consisting of: 0.1% to 10% by mass of Co, 0.01% to 0.5% by mass of Zr, 0.005% to 0.5% by mass of Ti, 0.001% to 0.5% by mass of Al, and 0.3% or less of S, the balance being Fe and inevitable impurities such as P, Cu, Sb, Te and Ce, wherein the P content is 0.1% or less by mass, and the total amount of the inevitable impurities is 0.7% or less by mass; said intermediate layer contains 0.025-0.15% by mass of B; the B content in said intermediate layer is 40% to 80% of the B content in said outer layer; and the total amount of carbide-forming elements in said intermediate layer is 40-90% of the total amount of carbide-forming elements in said outer layer, wherein the carbide-forming elements in said outer and intermediate layers (1, 2) are Cr, Mo, V, Nb and W, wherein the B content in the intermediate layer is determined as the concentration of B at a midpoint, Am, between inflection points, A1, A2, in a graph in which the concentration of B measured by inductively coupled plasma optical emission spectroscopy is plotted against the depth from the roll surface, wherein the inflection points, A1, A2, are the boundary regions between the outer layer and the intermediate layer, and between the intermediate layer and the inner layer, respectively, and wherein the total amount of carbide-forming elements in said intermediate layer is the total concentration of each carbide-forming element measured at the midpoint, Am. 0.1% to 3% by mass of Nb and/or 0.1% to 5% by mass of W, and/or at least one selected from the group consisting of: 0.1% to 10% by mass of Co, 0.01% to 0.5% by mass of Zr, 0.005% to 0.5% by mass of Ti, 0.001% to 0.5% by mass of Al, and 0.3% or less of S, the balance being Fe and inevitable impurities such as P, Cu, Sb, Te and Ce, wherein the P content is 0.1% or less by mass, and the total amount of the inevitable impurities is 0.7% or less by mass; said intermediate layer contains 0.025-0.15% by mass of B; the B content in said intermediate layer is 40% to 80% of the B content in said outer layer; and the total amount of carbide-forming elements in said intermediate layer is 40-90% of the total amount of carbide-forming elements in said outer layer, wherein the carbide-forming elements in said outer and intermediate layers (1, 2) are Cr, Mo, V, Nb and W, wherein the B content in the intermediate layer is determined as the concentration of B at a midpoint, Am, between inflection points, A1, A2, in a graph in which the concentration of B measured by inductively coupled plasma optical emission spectroscopy is plotted against the depth from the roll surface, wherein the inflection points, A1, A2, are the boundary regions between the outer layer and the intermediate layer, and between the intermediate layer and the inner layer, respectively, and wherein the total amount of carbide-forming elements in said intermediate layer is the total concentration of each carbide-forming element measured at the midpoint, Am.