A heavy-load radial tire comprises a tread portion, wherein in a tire meridian section including a tire axis under a normally inflated unloaded condition in which the tire is mounted on a standard wheel rim and inflate to a standard pressure but loaded with no tire load, the tread portion comprises a crown portion and a pair of shoulder portions each disposed axially outside the crown portion and including a tread edge, the crown portion has a crown profile being a circular arc of a radius of curvature TR1 of which the center is on a tire equatorial plane, the shoulder portion has a shoulder profile being a circular arc of a radius of curvature TR2 which crosses the crown profile at an intersection point P so that a tangent line on the shoulder profile at the intersection point P inclines at angle of not more than 7 degrees with respect to a tire axial direction, wherein the radius of curvature TR2 is 0.60 to 0.95 times the radius of curvature TR1, a plurality of sipes are provided in the shoulder portion, and each sipe extends from the tread edge toward the tire equatorial plane without going beyond the shoulder portion.