Based on the series of data of China's total water consumption and its major influencing factors from 1980 to 2015, a model for predicting the total water consumption is established through the statistical tests, and it is subsequently used to predict the extreme value and the relevant occurrence year in China. In order to verify the validity of the predicted results by the model, a method is put forward to predict the extreme value of the total water consumption in China using China's per capita comprehensive water consumption. On the basis of both the trend analysis of per capita comprehensive water consumption in typical foreign countries in recent decades and the characteristics of per capita comprehensive water consumption in China, the trend of comprehensive water consumption per capita in China is predicted. Then in the light of the peak population in China and its corresponding year, the calculated total water consumption in China is up to 650 billion m³ in the year about 2030, and it will decrease with the total population in China. The calculated results are consistent with the predicted ones by the proposed prediction model, which shows that the model for predicting the extreme value of the total water consumption in China, the relevant method as well the results are reasonable, and they can be used in other regions(provinces, cities and districts).