The invention discloses a supporting roll used for carrying out hot rolling on a 2250 leveling unit. The supporting roll comprises a roll
barrel arranged in the middle and roll necks arranged at two sides, the roll
barrel comprises a rolling area and harmful contact areas, the roll shape of the rolling area is a
linear section, the rolling shapes of the harmful contact areas at the two sides are both VCR curves in the shape of a parabola, and the two VCR curves are arranged at the two ends of the roll
barrel symmetrically by using the midpoint and the axis of the roll barrel as the original point and the X axis and using the Y axis as the
symmetric axis. The design method for roll barrel roll shape of the supporting roll used for carrying out hot rolling on the 2250 leveling unit comprises the following steps that 1, a working roll is determined to be a plain-barrel roll; 2, the overall convexity of the roll barrel is determined; 3, the distance between the bending-starting position of the roll barrel and the midpoint is determined; 4, a VCR roll shape curve model of the harmful contact areas is determined; 5, the integrated shape of the roll barrel is determined. The supporting roll used for carrying out hot rolling on the 2250 leveling unit has the advantages of reducing the number of the harmful contact areas, improving the roll-bending effect, enabling
contact pressure between rolls to be distributed evenly, improving strip shape quality and being small in working roll consumption, and can be widely applied to the technical field of hot rolling leveling.