Abstract: The influence of the heat generation rate and the Mo or noble metal content after nuclear fuel reprocessing on technique of high-level waste glass and waste management was analyzed based on the radioactivity and the chemical component of nuclear fuel changed with burnup of UO₂ fuel, and the numbers of high-level waste glass units were calculated by different burnups of UO₂ fuel. The calculated results indicate that heat generation rate caused by main components is not decisive factor for the waste loading of glass if the spent nuclear fuels are cooled longer than 8 a, Mo content is the decisive factor if the burnup is under 40 GW•d/tU, and the noble metal content is the decisive factor when the burnup is above 45 GW•d/tU. The linear relation exists between the number of glass units and the burnup of spent nuclear fuel, and the number of glass units generated increases with the burnup of spent nuclear fuel. With the increase of the burnup, the number of glass units calculated by Mo content and noble metal content is more than the number calculated by heat generation rate, thus, the number of glass units can decrease with the separation of Mo and noble metal. Increasing the burnup of spent nuclear fuel has barely influence on buffer storage time of high-lever waste glass units.