Naturally molted feathers provide a valuable tissue resource for avian research. Here we present a convenient and accurate species identification method for the naturally molted white feathers of six co-occurring Ardeid species, Egretta eulophotes, E. garzetta, Ardea alba, Bubulcus ibis, Mesophoyx intermedia and Ardeola bacchus, based on the polymerase chain reaction–restriction fragment length polymorphism of the partial mitochondrial cytochrome c oxidase subunit I gene. The resulting species-specific restriction patterns are easily distinguished by agarose gel electrophoresis. In this study, 81 of 88 naturally molted feathers noninvasively collected from heronries and 139 plucked feathers were all successfully distinguished, while the 7 feathers that could not be successfully distinguished by this method did not provide enough amplified products. This newly developed method for species identification of molted feathers will be useful for further studies on the vulnerable Chinese Egret and the other five co-occurring Ardeid species in East Asia.