The invention provides a continuous bending/straightening roll array curve of a plate billet/square billet continuous casting machine. The maximum value of bending/straightening stress is reduced to be a theoretical minimum value while the strain rate on a solid-liquid interface in a bending/straightening region is constant; a distribution function D(x) of liquid core thickness in a billet-pulling direction is obtained by calculating a machine temperature field, and the curvatures of points on a bending/straightening curve are confirmed according to distribution functions D1(x_bending) and D2(x_straightening) of liquid core thickness in a bending/straightening section obtained by coordinate transformation and fitting in the bending/straightening region, so that the curvatures, gradients and curvilinear equations of the points are worked out. The continuous bending/straightening roll array curve comprises a roll array curve of a straight-arc or all-arc type continuous casting machine, wherein the roll array curve ABCDEF of the straight-arc type continuous casting machine comprises a vertical section AB, a bent section BC, an arc section CD, a straightening section DE and a horizontal section EF; the roll array curve ADEF of the all-arc type continuous casting machine comprises an arc section AD, a straightening section and a horizontal section EF.