An organic light-emitting diode (OLED) display panel and a display device are provided. A pixel unit of the OLED display panel includes a first sub-pixel, a second sub-pixel and a third sub-pixel and further includes an anode layer, a cathode layer and an organic function layer. The organic function layer includes: a first emission layer (EML1) configured to cover at least two adjacent sub-pixels comprising the first sub-pixel; a carrier blocking layer (CBL) configured to cover the second sub-pixel and the third sub-pixel; a second emission layer (EML2) arranged at an area provided with the first sub-pixel and the second sub-pixel and configured to at least cover the second sub-pixel; and a third emission layer (EML3) configured to cover at least two adjacent sub-pixels comprising the third sub-pixel. The OLED display panel can improve the pixel density.