To provide a light extraction layer forming glass with which a light extraction layer exhibiting high light extraction efficiency can be formed at a low cost, and a glass substrate for an organic EL element using the same.

A light extraction layer 2 is formed by using glass 1 having a refraction index n_d of 1.8 to 2.2 and, in molar%, 0.1% or more of ZrO₂ and a Nb₂O₅ content of 15% or less, more preferably by using glass 1 comprising, in molar%, 20 to 35% of Bi₂O₃, 20 to 35% of B₂O₃, greater than 5% and less than or equal to 35% of SiO₂, 0 to 10% of Al₂O₃, 0 to 10% of ZnO and 1 to 8% of ZrO₂.