Abstract: In-situ leaching of uranium is an important method for the exploitation of sandstone-type uranium deposits in China.Sulfuric acid has become the preferred lixiviant for uranium acid in-situ leaching because of its low price, stable property and high leaching rate of uranium from ore.However, in the process of uranium acid in-situ leaching, there is a large amount of heat waste in the preparation of leaching lixiviant.Applying the heat in the processes that need to be heated for uranium in-situ leaching can not only help to improve the process effect, but also reduce the cost and energy saving.Based on theoretical calculation of sulfuric acid dilution heat release and laboratory and field tests, the effects of different processes and parameters on the utilization efficiency of sulfuric acid dilution heat are studied, and the optimal process parameters are determined.The results show that sulfuric acid dilution heat could improve the reverse-extraction effect of “eluex process”, eliminate emulsification, reduce the concentration of uranium in poor organic phase and residual water, and increase the temperature and evaporation rate of waste water in the evaporation tank of waste liquid treatment, so as to reduce the area of evaporation tank and reduce the cost.The principle and realization method of sulfuric acid dilution heat release is simple, and the performance is high efficiency and low consumption.Consequently, the application of sulfuric acid dilution heat in acid leaching uranium mining can effectively reduce the heat waste phenomenon in the process, which has obvious advantages.