Landscape genetics is an interdisciplinary field that has recently emerged between landscape ecology and population genetics., This new field emphasizes the impacts of the composition, spatial configuration, and underlying environmental gradients of landscapes on spatial population genetic structure, gene flow, and local adaptation. Being immature as an independent discipline, the basic principles applied in landscape genetics mainly come from molecular genetics, population biology, and landscape ecology. However, this field is characterized by its comprehensive methodological framework——an approach composed of genetic analysis with hypervariable molecular markers, remote sensing, analyses supported by geographical information systems and spatial statistics. Here, we introduce the basic concepts and the key questions of landscape genetics, outline the theoretical framework of this area, and identify its relationships with neighboring disciplines. In particular, we review an application domain of primary significance to landscape genetics, i.e. the genetic consequences of landscape fragmentation. Recent advances in this field include the spatial and temporal aspects of habitat fragmentation impacts on spatial population genetic structure and gene flow, life history strategies and species-specific responses to habitat fragmentation, as well as the selection effects of habitat fragmentation. By applying a cross-scale perspective, landscape genetics greatly contributes to our understanding of the impacts of landscape fragmentation on biodiversity.