is a genus of temperate bamboos (Poaceae: Bambusoideae) endemic to China, but little is known about its phylogenetic position and interspecific relationships. To elucidate the phylogenetic relationship of the bamboo genus , we performed genome-scale phylogenetic analysis of all seven species and one variety of the genus using double digest restriction-site associated DNA sequencing (ddRAD-seq) and whole plastid genomes generated using genome skimming. Our phylogenomic analyses based on ddRAD-seq and plastome data congruently recovered as monophyletic. The nuclear data resolved as the earliest diverged species, followed by , while the rest of can be further divided into two clades. However, the plastid and nuclear topologies conflict significantly. By comparing the results of network analysis and topologies reconstructed from different datasets, we identify as the most admixed species, which may be caused by incomplete lineage sorting (ILS) or interspecific gene flow with four sympatric species. This study highlights the power of ddRAD and plastome data in resolving complex relationships in the intractable bamboo genus.