[Objective] The spatial evolution of the productional-living-ecological space and the identification and measurement of land use relative conflict at Nanchang County of Nanchang City, Jiangxi Provonce from 2000 to 2020 were studied in order to provide a theoretical and practical reference for optimizing the pattern of territorial development and to achieve sustainable development of the social economy. [Methods] Based on three periods of remote sensing images and land use and land cover data in 2000, 2010, and 2020, with the productional-living-ecological space as the research basis, the remote sensing ecological index (RSEI) and landscape pattern index were used to construct a land use relative conflict measurement model. The temporal and spatial evolution patterns of land use relative conflict were analyzed by use of a transfer matrix and ArcGIS visualization. [Results] ① From 2000 to 2020, due to urban expansion and the influence of human activities, the living-productional space in Nanchang County expanded sharply, and the area of production-ecological space and ecological space decreased year by year. ② From 2000 to 2020, the mean value of RSEI decreased in Nanchang County, the overall quality of the ecological environment gradually decreased, and there was an ongoing expansion of the ecological environment degradation region. ③ From 2000 to 2020, the total area of land use absolute conflicts continued to increase, and from 2000—2010 to 2010—2020, the total area of land use relative conflicts decreased slightly. ④ From 2000 to 2020, the out-of-control areas of land use absolute conflicts were mainly located in the central urban area, and continuously expanded outward with the development of urbanization. From 2000—2010 to 2010—2020, the medium and high conflict areas of land use relative conflict shifted from the central urban area to the periphery, mostly in urban expansion areas during the last ten years. [Conclusion] In Nanchang County, the productional-living-ecological space has undergone a significant transformation. The quality of the ecological environment has declined. The absolute and relative land use conflicts have grown. Thus, strategies such as closely adhering to the red line of cultivated land protection, improving the ecological environment, and optimizing territorial spatial layout should be put into practice in order to optimize land use conflicts.