The invention discloses a hot-rolled steel plate and a preparation method thereof. The preparation method comprises the following steps of: roughly rolling, finely rolling, coiling, stacking-cooling and smoothly rolling a plate blank, wherein the initial stacking-cooling temperature is 450-750 DEG C, the end temperature is 0-100 DEG C, and the ductility during smooth rolling is 0.1-2 percent. The hot-rolled steel plate and the preparation method thereof have the benefits that the smoothness of the hot-rolled steel plate prepared by the preparation method is less than 2 mm/m, and the sickle camber is less than 2.5 mm/10 m, so that the residual stress of the hot-rolled steel plate can be effectively reduced, and further, the plate shape can be effectively improved; meanwhile, with the adoption of the preparation method disclosed by the invention, a special heat treatment production line as well as a cover type annealing device or a burial pit and other production equipment are not needed, and the hot-rolled steel plate has the characteristics of simple process control, strong adaptability, energy conservation and emission reduction, short production period, low cost and the like.