Abstract: The anatomical characteristics and phylogenetic relationships of secondary xylem of Magnoliaceae in China are described, including vessels、fibre-trachieds and rays. The ten genera may be divided into two subfamilies. The first subfamily is Magnoliodeae, including Magnolieae(tribe), which has Maglietia Bl., Manglietiastrum Law, Magnolia L., Parakmeria Hu et Cheng, Kmeria (Pierre) Dandy, Alcimandra Dandy six genera and Michelieae Law(tribe), which has Michelia L., Paramichelia Hu, Tsoongiodendron Chun three genera. The second subfamily is Liriodendroideae (Bark) Law, which only includes Liriodendron L. We analyzed the phylogenetic relationships by means of the differences of secondary xylem between the genera. The phylogenetic relationships of Magnoliaceae may be described as follows:[Magnolieae (Maglietia Bl., Manglietiastrum Law, Parakmeria Hu et Cheng, Kmeria (Pierre) Dandy→Magnolia L., Alcimandra Dandy)→Michelieae Law]→Liriodendroideae (Bark) Law.

Key words: Magnoliaceae, Secondary xylem, Phylogenetic relationships