A display module and a driving method thereof, and a display device are provided. The display module includes a backlight structure including a plurality of backlight partitions. The display module includes a first display mode and a second display mode. Resolution of the display module in the first display mode is greater than the resolution of the display module in the second display mode. In the first display mode, a quantity of the plurality of backlight partitions of the backlight structure is n1, and an area of one of the plurality of backlight partitions of the backlight structure is S1. In the second display mode, the quantity of the plurality of backlight partitions of the backlight structure is n2, and the area of one of the plurality of backlight partitions of the backlight structure is S2, with n1>n2, and S1