栅格是地球信息科学中大量使用的信息单元，其研究结果具有真正空间性的意义，而且可方便建立各种复杂数学模型。模糊综合评价方法是目前多指标综合评价实践中应用最广的方法之一。为了将模糊综合评价方法应用于空间栅格数据中，首先分析了模糊综合评价方法的原理及方法，然后以多源栅格数据为基础，以GIS空间叠置分析功能为手段，建立模糊综合评价GIS模型，并成功应用于实例中。实验结果表明，该模型能够较好地解决多源栅格数据的模糊综合评价问题。

Raster is used widely as a basic object in the geography information science, because products producted by raster have real spatial size and many math models are more easily built based on raster. Fuzzy comprehensive assessment is applied widely in the field of multi-factors evaluation application. Sometimes spatial data and spatial concept are fuzzy in geography information science, so fuzzy spatial analysis has gained more and more attention from researchers during the recent years, but fuzzy comprehensive assessment method is used rarely in multl-raster data. The theory of fuzzy comprehensive assessment is described in detail firstly. Then the GIS model about fuzzy comprehensive assessment is built based on multiraster data and spatial overlay analysis. The GIS model has been used in the urban air quality assessment successfully. The result of the instance shows that this model can well conduct fuzzy comprehensive assessment based multl-raster data.