Spatial overlay analysis is an important problem of spatial data analysis. Sometimes spatial data are fuzzy in Geography Information Systems and spatial database

so fuzzy overlay analysis has gained more and more attention from researchers during the recent years. Based on the interval value character of the attributes in GIS applications

the fuzzy map layers of fuzzy attribute data were described as interval valued fuzzy sets. Then an overlay analysis model of fuzzy raster map layers is proposed based on interval valued fuzzy sets. It improves the original fuzzy overlay analysis model

which based on classical fuzzy sets. With the basic operations of interval valued fuzzy sets the model can complete general fuzzy overlay and weighted fuzzy overlay. The weighted fuzzy overlay model will degenerate to general fuzzy overlay when the weights of fuzzy map layers are equal. The fuzzy overlay model can reduce the losing of attribute fuzziness through using interval value to represent the fuzziness

and the fuzzy overlay result accord with the cognitive and reasoning principle of people. The result of the instance shows that this model can well solve fuzzy overlay analysis between the map layers of interval value attributes.