Abstract: The wood anatomical characters of Acer trialum were described and illustrated,compared with wood anatomical characters of 17 species of this genus which have been researched.The result shows that woody ray with rich rhombus or square crystals is only seen in two species including Acer trialum and Acer cappadocicum among 18 species,and idioblast cells in woody ray are obvious characters different from the other species of Acer genus which have been researched.