The net water diversion of agriculture in Hetao Irrigation District was studied. Based on the data during 1982 to 2012 in Hetao Irrigation District, the characteristics of the net water diversion variability in 31 years were analyzed by using several statistic methods, such as ANOM, ANOVA, correlation analysis, time series analysis and survival analysis. In addition, the impact of annual precipitations and water-saving engineering projects was analyzed by the progress of Hetao Irrigation District developmental history. The forecasted net water diversion in Hetao Irrigation District would be about 44.5×10.8m3 in 2013, 44.18×108m3 in 2014 and 43.86×108m3 in 2015 by the time series analysis method. In current water-saving engineering project, the forecasted net water diversion would be from 35×108m3 to 55×108m3 by the survival analysis method. The net water diversion was influenced sharply by annual precipitation (more than 211.76mm, namely wet years) and water-saving engineering project. These two factors had a negative correlation with the net water diversion. Finally, the relationship between net water diversion and total investment of water-saving engineering project was discussed. The results provided an important foundation for the management of sustainable development in Hetao Irrigation District.