Abstract: Protecting high-quality concentrated and contiguous farmland is crucial for ensuring national food security. Taking Xingguo County in Jiangxi Province as a case study, an index system for evaluating comprehensive farmland quality was systematically constructed based on natural quality, site conditions, and ecological conditions. Utilizing the technique for order preference by similarity to an ideal solution（TOPSIS） comprehensive evaluation method, farmland quality was assessed. Farmland spatial aggregation characteristics were analyzed through farmland contiguity and spatial connectivity patterns, leading to the demarcation of permanent basic farmland based on comprehensive quality and connectivity. Results indicated that Xingguo County’s farmland quality was divided into 4 grades, with areas of 6 204.95 hm~2, 16 031.72 hm~2, 19 321.79 hm~2, and 3 573.76 hm~2, representing 13.75%, 35.52%, 42.81%, and 7.92% of the total farmland area respectively, with the majority falling in the medium quality range at 78.33%. In terms of farmland connectivity, the area was classified into 5 contiguity levels, with areas of 24 731.44 hm~2, 6 199.73 hm~2, 3 131.54 hm~2, 7 397.71 hm~2, and 3 671.80 hm~2, accounting for 54.80%, 13.73%, 6.94%, 16.39%, and 8.14% of total farmland area, revealing varying degrees of fragmentation. Farmland of grade three or above and contiguity level four or above was designated as permanent basic farmland, covering 37 029.62 hm~2, or 82.05% of the total area. This delineation achieved the goal of “overall stability, optimized layout, and improved quality” compared with previous permanent basic farmland designations.