The invention relates to the field of glass manufacturing, and discloses a glass composition, glass low in impurity content and a preparation method and application of the glass. The composition comprises, by weight, 50-64% of SiO2, 14-24% of Al2O3, 0-7% of B2O3 and P2O5, 0.5-7% of MgO, 1-10% of CaO, 0-9% of SrO, 0.1-14% of BaO, 0.1-5% of ZnO, 0.1-4% of TiO2, 0.1-7% of BaO, 0.1-5% of ZnO, 0.1-4% of TiO2, 0.1-7% of Y2O3, La2O3 and Nd2O3 and 0.05% of R2O, wherein R2O is the total content of Li2O, Na2O and K2O. The composition satisfies the following conditions that the temperature T100 corresponding to the viscosity of 100 P is 1730 DEG C or above; the surface tension is smaller than 420 mN / m at the temperature of 1300 DEG C. The glass prepared through the glass composition and the preparation method of the glass low in impurity content has the advantages of being low in impurity content, simple in preparation process, low in cost and the like.