Abstract: A phylogenetic analysis of the Magnoliaceae was performed based on sequence data of the chloroplast matK gene in 57 species representing 11 genera. The results show that (1) the genus Magnolia might be a polyphyletic group; (2) Magnolia subgenus Yulania should be elevated to the generic rank; (3) the section Splendentes in Magnolia subgenus Magnolia had a very close relationship with the two American species in the section Rytidospermum, M. macrophylla and M. dealbata, and the section Gwillimia was close to the section Theorhodon; (4) the generic status of the genus Talauma was highly supported when its Asian section Blumiana was shifted to Magnolia; and (5) the genus Parakmeria formed a clade with the two genera Kmeria and Manglietiastrum; and they all had a close relationship with Magnolia subgenus Yulania and the genus Michelia. The position of flower buds, a major feature which had been previously employed to differentiate Michelieae and Magnolieae, turned out to be an unreliable character obscuring the distinction between the two tribes. The traditional circumscription of these two tribes should be emended. Magnolia and Michelia would become two well-defined genera when the subgenus Yulania was segregated from Magnolia to be treated as an independent genus.

Key words: Magnoliaceae, Magnolia, matK gene, phylogenetic analysis.