OLED (Organic Light Emitting Diode) device and display device

The invention discloses an OLED (Organic Light Emitting Diode) device and a display device, relates to the technical field of display, and aims to solve the problem of poor display effect of the display device since the light color of the OLED device is nonadjustable. The OLED device comprises a substrate base plate, an anode, an organic functional layer, a cathode and a thermal expansion layer, wherein the anode, the organic functional layer and the cathode are successively overlapped and arranged above the substrate base plate; and the thermal expansion layer is positioned on the side surface, which is opposite to the organic functional layer, of the anode, and/ or the thermal expansion layer is positioned on the side surface, which is opposite to the organic functional layer, of the cathode, wherein the thermal expansion layer is a transparent thermal expansion layer. Therefore, the temperature of the thermal expansion layer changes to regulate the thickness of the thermal expansion layer so as to regulate the wavelength of light which passes through the thermal expansion layer, the light color of the OLED device is regulated, and the display effect of the display device is improved. The OLED device provided by the invention is applied to the display device.