The strategic ultimate aim of the dynamic balance maintenance of total cultivated land is not only to maintain the dynamic balance of cultivated land quantity level, but also to ensure the dynamic balance of cultivated land quality level. It’s necessary to monitor change of cultivated land quality level and build cultivated land quality early-warning system for maintaining the dynamic balance of region’s cultivated land quantity level. Taking the Jintan City as empirical study area and utilizing the former study results, this research has designed and carried out function, database content, index systems, alert degree determination methods and early-warning results trend extrapolation methods of cultivated land early-warning system based on evaluating cultivated land quality and analyzing its’ change characteristics using GIS and mathematics methods. The results show that: cultivated land quality early-warning system can prevent cultivated land quality from declining and maintain the dynamic balance of total cultivated land, because of its dynamic, real time monitoring function. Furthermore, alert degree determination of cultivated land quality early-warning system indicates the degree of early-warning sign index deviating from the normal status, consequently, early-warning system can provide obvious control point for regulating the regional dynamic balance of total cultivated land.