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Three indexes, gross irrigation water productivity (Pg), canal irrigation water productivity (Pc), and net irrigation water productivity (Pn), were built. The data from 443 major irrigation areas throughout China were collected in 1998, 2005 and 2010, and the spatial and temporal variation of irrigation water production and the relationship between the indexes were analyzed. The results showed that the national average value of the three indexes were 1.361, 2.532 and 2.989kg/m3. and the indexes in each province showed a trend of increasing with time. The municipalities directly under the central government increased large while grain producing areas in Yangtze River Basin were small. The irrigation water productivity indexes in representative years aggregated obviously in the area of Huang-Huai-Hai plain as a high value area while the low value areas were in south, northwest and northeast of China. There were significant linear correlations among Pg, Pc and Pn, respectively. The determination coefficients were greater than 0.90. Any index can be used as the representative of regional irrigation water productivity in the country.