Farmland plays the important role and provides the function of basic food supply, but due to the impact of the expansion of urbanization, its uses have been converted to other purposes. Apart from providing food, farmland is also capable of supporting a range of biological activities, water storage and flood control. In addition, it also aids in slowing down greenhouse gases emissions and maintains other environmental and ecological functions. Therefore, based upon the impacts from production and urban development on lands, it is necessary for us to perform a sustainable land planning. In view of this, this paper has utilized the geographic information system (GIS) as a basic space analysis method to conduct the regional planning on broken, perforated and the cutting of farmlands, and integrate them with living, production, ecological and other aspect indicators so as to carry out space overlay mapping and suitability analysis. Through farmland resources and space planning, this paper tries to review the current use of farmland resources, adjust the unsuitable sites, and adverse environmental conditions or improper use of farmlands by coordinating with state land functions and divisional simulation results. This paper uses the District of Tainan as an example with the purpose of confirming the structural operability of this method, and to establish an integrated space technology in sustainable planning on farmland resources and spaces.