A backlight module and a display device are provided. The backlight module includes a first data line, a second data line, and a light-emitting diode group. The light-emitting diode group includes two or more light-emitting diode units. A voltage at a connection point between a n-th light-emitting diode unit and the first data line is defined as Vn. A voltage at a connection point between the n-th light-emitting diode unit and the second data line is defined as Un. In response to Vi is greater than Vj, Ui is greater than Uj.