The backlight system comprises a light source module, a control circuit board, a current-balancing circuit board, and a plurality of high voltage lines. The light source module comprises a plurality of light sources. The control circuit board is configured with a control circuit for converting a received signal to a high voltage signal to drive the light source module. The current-balancing circuit board is configured with a four-layered structure and copper foils within the four-layered structure form a plurality of capacitors so as to balance current flowing through the light sources. The plurality of high voltage lines connect the control circuit board to the current-balancing circuit board.