The National Crop Genebank currently conserves 368 accessions of wild soybean (Glycine soja) from Fujian Province, collected between 1980 and 1982 across 26 counties (cities and districts) within four prefecture-level cities: Nanping, Sanming, Longyan, and Ningde. More than 40 years later, we conducted a supplementary field survey and germplasm collection in 2025, covering 25 county-level administrative regions,with a particular focus on areas with no prior accessions deposited in the Genebank. For the first time, wild soybean populations were documented in three additional prefecture-level cities: Fuzhou, Quanzhou, and Zhangzhou. We collected germplasm from 19 new county-level regions, representing a 73.08% increase in the number of county-level regions, and obtained a total of 75 populations, a 20.38% increase over the province''s previously held accessions. Two novel morphotypes were newly newly discovered in this survey: a bloom-lacking glossy seed coat type and a long-inflorescence type. This survey also revealed that the southern distribution limit of wild soybean in Fujian has shifted markedly southward relative to historical records. The new southern limit in southeastern Fujian is located in Changle District, Fuzhou City, representing a southward shift of approximately 93 km in latitudinal straight-line distance relative to the former southern limit at Xiapu County, Ningde City. The new southern limit in the northern part of southern Fujian is in Yongchun County, Quanzhou City, representing a southward shift of approximately 90 km in latitudinal straight-line distance relative to the former limit at Youxi County, Sanming City. The new southern limit in southwestern Fujian is in Nanjing County, Zhangzhou City, representing a southward shift of approximately 50 km in latitudinal straight-line distance relative to the former limit at Shanghang County, Longyan City. The discovery of the southern marginal populations in Changle District of Fuzhou City and Nanjing County of Zhangzhou City has expanded our understanding of the distribution of wild soybean (Glycine soja) in China: this species was previously confined to regions north of the mid-subtropical zone and is now confirmed to occur in the south-subtropical zone. This finding provides the latest evidence for the conservation of wild soybean resources in southern China, germplasm collection campaigns, and floristic regionalization of the genus Glycine.