Abstract:A concept of “open space” in the anther tissue structure of foxtail millet (Setaria italica) and wheat (Triticurn aestivum) has been suggested. In the late stage of anther development, “open spaces” are formed beneath the epidermis at the opening place between two anther chambers. They get through the bilateral edge of the anther longitudinally making the chambers easy to open. “Open space” is considered to be one of the inner factors of anther opening in foxtail millet and wheat.