An organic light-emitting diode (OLED) display panel and an OLED display device are provided. The (OLED) display panel includes a first substrate; a first electrode layer disposed on the first substrate and including a plurality of first electrodes; a plurality of light-emitting devices disposed on a surface of the first electrode layer far away from the first substrate and having m number of colors, where m is a positive integer; and a second electrode layer disposed on a surface of the plurality of light-emitting devices far away from the first electrode layer. One light-emitting device corresponds to one color, and given a predetermined value of brightness, the light-emitting devices of two different colors are configured to have a predetermined absolute value of a threshold voltage difference.