The invention provides an OLED display device. A plurality of projections are arranged on one surface of a side, positioned close to an OLED device, of a cover plate substrate; outer surfaces of the cover plate substrate and the plurality of projections are wrapped with heat conduction layers, heat radiation area and heat radiation efficiency of a cover plate can be increased, service life of the OLED device can be prevented from being reduced due to heat accumulation, and the cover plate is enabled to be high in mechanical strength; a first heat conducting and light shielding layer including graphene and light shielding material is coated on an outer side of sealing gum, on an area, positioned outside the sealing gum, of the cover plate and on an area, positioned outside the sealing gum, of a base plate; a second first heat conducting and light shielding layer is coated on an area, positioned outside a part corresponding to the OLED device, of a bottom part of the base plate; the OLED display device can be prevented from all-around light leakage while air tightness of the OLED device can be enhanced, external moisture can be effectively prevented from permeating the OLED device, the service life of the OLED device can be prevented from being affected, heat radiation efficiency of the OLED display device can be further improved due to excellent thermal conductivity and electrical conductivity of the graphene material, the OLED display device can be free from static electricity, and product quality can be improved.