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From ancient times to the present, food issues are always the material basis of human’s survival and social development. And of the way to increase food production capacity, is to increase the areas and improve the quality of arable land as security. However, in recent decades the area of arable land is still in continuous decrease. The arable land resources in China still face a very severe situation. Thus it’s important to protect and optimize the quality of arable land. The paper discussed the theory of land evaluation. According to the process of quality evaluation of arable land, it developed a arable land evaluation system based on the section data of Xiping County. The main jobs of the paper are as follows:(1) Data acquisition and processing. The main job is to collect the soil maps, district maps, topographic maps and other related socio-economic data of the study area. Then use ArcGIS9.2 which is the geographic information systems digitize the images, and establish the basic geographic information database; use ENVI program which can interpret the remote sensing images to get the land-use types of data.(2) It also contains the study of arable land quality evaluation. On the basis of the discussion of the factor selection, the determination of the factor’s weight, the single factor evaluation and multi-factors integrated evaluation; it overlays the land-use type maps, soil maps and district map as the basic map. And according to the actual situation of Xiping County, it selected seven indicators for evaluation. There are several steps to determine the single factor’s membership functions; first it should be given the scores by experts, then obtain the factor’s membership functions with a nonlinear curve-fitting method with SPSS program, and the obtained functions curve and the scatters can score a good match. Finally, it use Analytical Hierarchy Process method to determine the weight of the factors, then can obtain the scores of multi-factors by the weighted average of the result of single factors, as thebasis of the grade classification.(3)Design and implement the arable land quality evaluation system. It based on ArcGIS Engine, use of visual programming language VC++6.0, designed and implemented the "arable land quality evaluation system". The system mainly achieved three major functions which are the map browsing, spatial analysis and thematic evaluation. The first function includes the common function of usual GIS system. And spatial analysis part implements the stacking analysis, spatial interpolation, as well as format conversion, such as vector images. The thematic evaluation includes two modules which are the single factor assessment and multi-factors integrated evaluation. The key part of the single factor evaluation is normalized the data by the membership functions, first of all, read the membership functions and the sampling points in the database, then use the membership function of the corresponding indicators to calculate the data, the results stored in another field, for interpolation operations, etc. The key part of comprehensive evaluation is the use of AHP method to determine the weights of the factors, in order to process a better scalability, by adding factors of soil properties, the natural environment factors, socio-economic conditions and other factors, and computing in four tiers. In addition, according to the factors which are belonging to different ingredients, the system can compute and store the weights of the factors. In this way, regardless of the type of ingredients which the selected factors belong to, as long as there have the judgment matrix, it can calculate their weights.The evaluation system is not dependent on the data, as long as the users update the database, the system can be common to other regions of the evaluation. The whole system has a friendly user interface which is easy to use. And it can evaluate the arable land in several steps, form the initial sampling points to the final map, the system implement every step of the process. If the users have data, they can easily achieve the process of arable land quality evaluation.(4)The arable land quality assessment is based on the evaluation of vector maps. That is, from basic map to the final evaluation results are all vector data. Using the vector data has several advantages: the results of its evaluation are clear, high accuracy of orientation, the features of the map are obvious, the distribution is near and the amount of data is small. Then use ArcGIS drawing the maps and then we can see the picture of the score distribution of each factor and the final grades of the arable land.