The present disclosure provides an organic light-emitting diode (OLED) display panel and an OLED display device. The OLED display panel including a substrate disposed of a first flexible layer, a first barrier layer, and a second flexible layer sequentially. So that the water and oxygen be blocked by the first barrier layer after passing through the first flexible layer, and be blocked by the second barrier layer after passing through the second flexible layer. Therefore, improving the water and oxygen blocking ability of the OLED display panel to solve a technical problem of poor water and oxygen blocking abilities.