A control method of a display panel and a display device are provided. In the method, at least one binding-point grayscale value is obtained at first; an initial-state control parameter, an initial-state brightness parameter, and a reference brightness parameter of a to-be-regulated region are determined according to each of the binding-point grayscale value; and a relative compensation brightness parameter of the binding-point grayscale value is determined according to the initial-state control parameter, the initial-state brightness parameter, and the reference brightness parameter of the binding-point grayscale value when a ratio of the initial-state brightness parameter to the reference brightness parameter is not within a preset range.