To provide an organic EL device which, with simple configuration, exhibits a high brightness, a high light-emitting efficiency and a long life span in organic light-emitting layers for all colors, and has excellent conservation stability to heat. An organic EL device of the present invention has a laminate comprising an anode and a cathode with an organic light-emitting layer interposed therebetween. The organic light-emitting layer is made of a high-molecular-weight light-emitting material. Further, the cathode comprises a first layer made of fluoride or oxide of an alkali metallic material, fluoride or oxide of an alkali earth metallic material, or complex or compound of an organic material, and a second layer made of a magnesium alloy. Here, the first layer and the second layer are sequentially deposited on the organic light-emitting layer.