Abstract:Two exotic weeds, Brachiaria platyphylla (Munro ex C. Wright) Nash and B. plantaginea (Link) Hitchc, are firstly reported in China. They share the characters of the lower glume adaxial and the upper lemma obtuse with Chinese Brachiaria species, without the characters of the abaxial lower glume, long mucro upper lemma of Urochloa species. The taxonomic differences among these two new record grasses and the other Brachiaria species from China are edited in one key. Their potential invasion risks are discussed.