An organic light-emitting diode (OLED) structure and a manufacturing method thereof are provided. The OLED structure includes a substrate, a metal layer, a passivation layer, an anode, and an OLED functional layer. By setting the OLED functional layer to form a PN junction with low impedance. The PN junction and a conductive layer with high impedance constitute a resistive divider, and the PN junction is turned on by adjusting a high-voltage direct current (DC) input source and a low-voltage DC input source. Because the resistance of the PN junction is very small, the potential of the cathode can be approximated to the potential of the low-voltage DC input source according to resistive voltage divider rule, and the low-voltage DC input source uses low-resistance metal, which can effectively avoid the problem of IR drop.