An organic light-emitting diode (OLED) display panel and an OLED display device are provided. The OLED display panel comprises a first substrate; a first electrode layer disposed on the first substrate and including a plurality of first electrodes; a hole transport layer disposed on a surface of the first electrode layer far away from the first substrate, and formed by a first hole transport material and a second hole transport material having different carrier mobility; a plurality of light-emitting devices disposed on a surface of the hole transport layer far away from the first electrode layer and arranged in correspondence with the plurality of first electrodes respectively; an electron transport layer disposed on a surface of the plurality of light-emitting devices far away from the hole transport layer; and a second electrode layer disposed on a surface of the electron transport layer far away from the plurality of light-emitting devices.