Disclosed are an organic electroluminescence element with significantly improved light extraction efficiency and improved film properties and an illumination device that uses said element. The organic electroluminescence element has a transparent electrode, an organic electroluminescence layer, and a cathode sequentially stacked on a transparent base material. The element is characterized in that the transparent base material is a transparent resin film, there is a hard coat layer on both sides, the respective refractive indices satisfy the expressions (1)-(4), and there is a function to scatter light to the light emission side with respect to the organic electroluminescence layer. Expression (1): −0.2≦n(H1)−n(A)≦0.2, Expression (2): −0.1≦n(H1)−n(B)≦0.1, Expression (3): −0.1≦n(H2)−n(B)≦0.1, Expression (4): −0.1≦n(H1)−n(H2)≦0.1. In the expressions, n(A) is the refractive index of the transparent electrode; n(H1) is the refractive index of the hard coat layer (on the transparent electrode side); n(H2) is the refractive index of the hard coat layer (on the side opposite the transparent electrode); and n(B) is the refractive index of the transparent resin film.