The American mink (Neovison vison) is known as a successful invader in Europe, impacting native species' population sizes and habitats. This study investigates the genetic structure and diversity of American mink populations in France over two decades (1997-2016). The analysis involves feral and farmed mink sampled from various regions, using ten autosomal microsatellite loci for genotyping. The objective is to identify genetic clusters, especially between feral and captive individuals, and assess changes in genetic structure over time. Results reveal high genetic diversity and low inbreeding within populations, with evidence of genetic structure influenced by both farm releases and feral colonization. The study highlights the reflection of the genetic structure in farm populations in the feral populations within the first period (1997-2007), and a decline of a lineage over time in the second period (2007-2016) with the emergence of a new genetic cluster, potentially influenced by factors such as selection, phenotypic changes, and interactions with pathogens. Overall, this research contributes to understanding the dynamics of American mink populations in France and their genetic variability, emphasizing the importance of ongoing monitoring and management efforts to mitigate the impact of this invasive species.