The present disclosure provides a backlight module and a display device. The backlight module includes a substrate layer and light-emitting diode (LED) light bars equidistantly disposed on the substrate layer. Wherein, each of the LED light bars includes a signal line and LED lamp beads. The LED lamp beads are arranged on the signal line and electrically connected to the signal line. Wherein, a distribution density of the LED lamp beads gradually decreases from a low-level end of the signal line to a high-level end of the signal line.