Abstract: In this paper,a method of graphic overlay analysis from the grid data is introduced.Four technical processes are proposed:A way of chain topology for converting the vector data into grid data.A specific encoding for data compression of grid mode and and its effective storage.Based on the fuzzy theoory a mathematical model of multielement comprehensive analysis is established.A border following program using in the grid merging after attribute data types overlay analysis.Finally,an application of land-use evaluation for buji(a town in Shen-zhen city) town planning is shown to examine the proposal model of grid data graphic overlay by the author.