In order to predict many important physical phenomena in a large-size glass during annealing the application of the finite element solution of heat transfer problems to the determination of the tempe ature distibution within axisymmetric glass being annaeled (the temperature change is slow) has been suggested for the first time in this paper. According to above result, this paper also suggests the calculation method of the nonuniformity of refractive index due to the nonhomogeneous structure of annealed glass, thus overcoming previous difficulty in the oaloulation.