Recently, Mr. Muto of the Gifu Agric. Exp. Sta. observed that the edible roots of Burdock "Gobo" (Arctium lappa L.) cultivated in Gifu district were severely injured by the larvae of an Agromyzid fly. This is apparently a new pest of Burdock and its bionomics and control measures are being studied by him. After examination of the specimens which recieved from Mr. Muto, I came to the conclusion that this Agromyzid is undescribed form. The present paper deals with the taxonomical study of this fly. The terminology used here are taken from Dr. Frick (1952) with minor exceptions. I wish to express here my sincere thanks to Mr. Toshiro Muto of the Gifu Agricultural Experiment Station for the gift of the specimens, and also to Prof. Dr. Chukichi Harukawa of the Okayama University for his kindness in reading through this manuscript.