Abstract: Basing on the research advancement of taxonomy for Malus trilobata Schneid. , using the theories and methods of phylogeny􀀁phytogeography, the authors found that Malus trilobata developed independently from Malus laoensis Chev. , one of the most primitive species of Malus Miller, after they separated from a homogeneous flora in early time. Malus trilobata is one of the most closely related taxa of the genus Malus Miller and it should be originated in theCretaceous period. As a conclusion, the author suggested that Malus trilobata Schneid. be named Cormus Decisne.

Key words: Rosaceae, Cormus Decisne., Malus trilobata Schneid., Taxonomy, Homogeneous flora, The Cretaceous period