"Drymaria villosa" Cham. & Schltdl. (Caryophyllaceae) is recently recognized from northern and central Taiwan as a newly naturalized plant. It is a newly naturalized species as a potentially aggressive weed in Taiwan. Description, illustration and distribution map of this species is provided. A key to the genus "Drymaria" in Taiwan is also given. In outline, "Drymaria villosa" Cham. & Schltdl. is similar to D. cordata (L.) Willd. ex Roem. & Schult. They are broad-ovate to reniform leave blade, but differs in stems and leaves pilose.