In this paper, the difference of grain production among cites was calculated by adopting Gini coefficient and Theil index, methods of correlative analysis were adopted to calculate the correlations between grain production and time variable to analysis change pattern of grain production difference among cities, based on grain production statistical date of Jiangxi Province from 2000 to 2010. The result showed: (1) The trend of grain production showed reduce-increase, the production growth rate was weak, the trend of total sown areas of grain crops’ change was similar to grain production. (2)There was a good consistence between Gini coefficient and Theil index in reflecting the degree of the difference of grain production among cities in Jiangxi Province, the linear regression results about Gini coefficient and Theil index with time variable were as followes: G=0.0039(t-1999)+0.1477 and T=0.0021(t-1999)+0.0341, the correlation coefficient was 0.949 and 0.956. (3)The tendency of difference of grain production among cities in Jiangxi Province presented expansion trend. (4)Paddy, as major grain crop, its contribution on the Gini coefficient was biggest, more than 95%. (5)The contribution of paddy to Gini coefficient tends to rise at first, then fall, and becomes flat at last. (6)Based on grain production in different cities and result of analysis on time variable regression, the province can be divided into four districts, which was a very significantly increased district, significantly increased district, a very significantly decreased district, the proportion of stable district.