Abstract:The perforation plates of vessel elements in secondary xylem of Liriodendron which include 2 species were observed in detail by scanning electron microscope (SEM), and many details were observed that were not reported by light microscope. Reticulate scalariform perforation plates exist in Liriodendron, and the simple perforation plate, epledroidforation and pit membrane remnants were observed in L. tulipifera. The results showed: (1) for Liriodendron chinense (Hemsl.) Sarg., the perforation plates are typically scalariform with a few bars and reticulate scalariform perforation plates, but occasionally are reticulate perforation plate; (2) for Liriodendron tulipifera, the perforation plates are scalariform perforation plates and reticulate scalariform perforation plates, but occasionally are simple perforation plates; (3) part of scalariform perforation plates in L. tulipifera with wider and more bars; (4) perforation plates with a few bars are more in L. chinense than in L. tulipifera; (5) the perforated plates in L. tulipifera are more inclined than in L. chinense; (6) epledroidforation and pit membrane remnants were observed in L. tulipifera. The conclusion is that the perforation differentiation of L. tulipifera is more violent.