Abstract: The vessel elements and their perforation plates in the secondary xylem of stem of the four genera in Lardizabalaceae were observed under scanning electron microscope (SEM). The results showed that, (1)simple perforations were found on the end wall of the vessel element in four species; (2)Sinofranchetia was distinguished from the others by perforation types on the end wall: reticulate, scalariform, simple, reticulate-scalariform, reticulate-simple, scalariform-simple and reticulate-scalariform-simple perforations; the membrane remnants in perforations were various from web, flake and thread; Sargentodoxa and Holboellia shared some characteristics of scalariform, scalariform-simple and simple perforations plates on the end wall of the vessel element; only simple perforations plate was found in Stauntonia; (3)scalariform and reticulate-scalariform perforations appeared on the lateral wall (except Stauntonia); (4)spirally thicken presented on the lateral wall of the vessel element in Stauntonia. The new characteristics of vessel element of genera can provide important basis for phylogeny analysis in Lardizabalaceae.

Key words: Sinofranchetia chinensis, Sargentodoxa cuneata, Holboellia grandiflora, Stauntonia chinensis, Lardizabalaceae, vessel element, perforation plate