The establishment of the Department of Rare Diseases at Peking Union Medical College Hospital(PUMCH)is a landmark in the disciplinary development of the rare diseases.The establishment of the department will booster the prominence of the influence and leading position of the PUMCH in the field of rare diseases.In addition,the department is instrumental in the development of the hospital of high-quality.The department aims at delivery of better medical care for patients with rare diseases,the training of special-ists in rare diseases,and avancement of the preventing and treating rare diseases in China.This paper pre-liminarily discusses the working basis,significance and discipline development plan of the department of rare diseases at PUMCH.