Today, with more than 11,000 living species, birds are the most species-rich class of tetrapod vertebrates and have been widely used as models in broad research disciplines, including biology, genetics, developmental biology, animal behavior, ecology, biogeography and so on. The Bird 10,000 Genomes (B10K) Project, as a community-based large-scale sequencing project, has been running for many years to generate representative draft genome sequences from all extant bird species. The B10K project will allow the completion of a genomic level tree of life of the entire living avian class, decode the link between genetic variation and phenotypic variation, uncover the correlation of genetic evolutionary and biogeographical and biodiversity patterns across a wide-range of species, evaluate the impact of various ecological factors and human influence on species evolution, and unveil the demographic history of an entire class of organisms. Given all these aims, we are carrying out the project in four phases (order phase, family phase, genus phase, and species phase). Each phase focuses on the completion of milestones at hierarchical levels of avian classification. We envision this project will have significant scientific and public impact that will change our understanding of avian biology and evolution, which in turn will affect our understanding of other organisms and open doors to new areas of research.