Ecological land is a major supplier of ecosystem services, and plays a key role in controlling regional eco-environmental quality. Protection of ecological land significantly promotes the sustainable development of society, the economy, ecology, and regional ecological security. The present research used Yixing city as a case study area, which is located in the southern part of Jiangsu Province. Firstly, following previous research into the relationships between ecological land use classification and current land use classification, the vector data for ecological land were acquired from the current land use vector data for Yixing. Secondly, the landscape security pattern theory and the model of minimum cumulative resistance were used to construct a comprehensive landscape security pattern after systematic analysis of the soil and water conservation, biodiversity protection, vernacular culture protection, and natural landscape protection processes related to ecological land. The overall landscape was then classified into four grades. Finally, the comprehensive landscape security pattern and the current ecological land maps were overlaid. The current ecological land areas were classified into lower, low, middle, and high security pattern levels, and these areas covered 50528.29 hm², 69942.53 hm², 34777.44 hm² and 2335.07 hm², respectively, which accounted for 32.07%, 44.38%, 22.07%, and 1.48% of the total ecological land area, respectively. In the lower security pattern level ecological land, forest land and cultivated land, located in the southern hilly area, were the priority use types. In the low security pattern level ecological land, cultivated land, and water surrounding the city were the priority use types. In the middle security pattern level ecological land, water and cultivated land that was away from the city were the priority use types, and in the high security pattern level ecological land, water that was located far from the west bank of Taihu Lake was the only land use type. This study makes recommendations for improving ecological land based on the condition of the different land use types found in the ecological land areas. Identifying the landscape security pattern levels for ecological land and giving priority to protecting ecological land are the main approaches used to expand ecological land in urban construction areas in regions that are undergoing accelerated urbanization. This study provides scientific guidance that will aid urban sustainable development decision making, and land use planning and management in Yixing. It also provides scientific methods for ecological land planning that could be used in other areas with similar land conditions.