Along with the process of urbanization,the old-town renewal has become the top task in the city construction.Directed by quantitative analysis of city's economy,this paper puts forward a new conception and model of development capacity for old city renewal,established land class evaluation system and AHP model to determine the land class and its evaluation factors.Restricted by the old town's eco-environment and social environment,and targeted by its economy,this paper suggests that the upper limit model of the old city's development capacity should be decided by its eco-environment volume and social environment,and the lower limit model should be determined by the market economy,thus the renewal can see the economy,society and environment proceed orderly and harmoniously.Upon the platform of ARCGIS with considering Nanyang old town renewal planning and design,this paper has drawn a digital map for old town renewal development intensity,and explores tentatively the proper development capacity under the platform of GIS.