Abstract: The taxonomical history of the woody group(peonies) in the genus Paeonia is reviewed in the present paper. The group is endemic to China, but Paeonia suffruticosa is commonly cultivated throughout the north temperate region and has long been known as “the King of Flowers” in China. However, the taxonomy of the group had been neglected before the 1990' s. Since 1990, a number of new species and subspecies have been published. With the support from the National Geographic Society, the senior author of the present paper and his coworkers have made expeditions to all parts of the distribution area of the group, visited all the type localities and sampled a total of 64 populations. Based on the character analysis and examination of the type specimens or photos, each taxon is reviewed with its name checked nomenclaturally, and finally the taxonomy of the whole group is revised. As a result, eight species, three of which each contains two subspecies, are recognized. They are Paeonia suffruticosa Andrews subsp. suffruticosa and subsp. yinpingmudan D. Y. Hong, K. Y. Pan et Z. W. Xie, P. jishanensis T. Hong et W. Z. Zhao, P. qiui Y. L. Pei et D. Y. Hong, P. ostii T. Hong et J. X. Zhang, P. rockii (S. G. Haw et L. A. Lauener )T. Hong et J. J. Li subsp. rockii and subsp. taibaishanica D. Y. Hong, P. decomposita Hand.-Mazz. Subsp. decomposita and subsp. rotundiloba D. Y. Hong, P. delavayi Franeh. and P. ludlowii (Stern et Taylor)D. Y. Hong. P. baokangensis Z. L. Dai et T. Hong and P. yananensis T. Hong et M. R. Li are considered as hybrids between P. rockii and P. qiui and between P. rockii and P. jishanensis respectively. In addition, the reduction of a number of names recently published to synonyms is explained.

Key words: Paeonia, Section Moutan, Taxonomical history, Revision