A color-changing device and a control method thereof. The color-changing device comprises a first substrate layer, a first conductive layer, a color-changing layer, a second conductive layer, and a second substrate layer that are stacked in sequence. Edges of two ends of the first conductive layer are respectively provided with a first bus bar (1) and a second bus bar (2), and a third bus bar (3) and a fourth bus bar (4) are respectively provided at edges of two ends of the second conductive layer. The color-changing device also comprises at least one partition structure, comprising at least two boundary bus bars and at least one partition bus bar located between the two boundary bus bars, the partition bus bar and the boundary bus bars being respectively located on different conductive layers. The control method is used for controlling the transmittance state of the color-changing device; a color-changing control signal is applied to the color-changing device; a target voltage is determined according to a transmission rate state type carried by the color-changing control signal received by the color-changing device; the target voltage at least comprises voltage values corresponding to the first bus bar (1), the second bus bar (2), the third bus bar (3), the fourth bus bar (4), the boundary bus bar, and the partition bus bar, respectively; and the transmittance state of the color-changing device is adjusted according to the target voltage. A voltage abrupt change is realized at the partition structure composed of the boundary bus bar and partition bus bar, thereby achieving the partition color change of the color-changing device.