Juji Kii graduated from Mechanical Engineering Course of Tokyo University (1911).
Juji Kii entered Railwayv Bureau (1912) and served as chief of Rolling Stock Section of Nagoya Railway and chief of Machinery Section of Oi Plant of Tokyo Railway and director of Construction Bureau of Railway Ministry, resigned (1939). He became senior managing director of Shibaura Kyodo Kogyo (Industrial) Company and chairman of Zenkoku Jidosha Seibi Kyokai (National Motorcar Repairing Association). Made official tour of Europe and America (1938). Assumed additional posts of lecturer at Tokyo University and director of Japan Rolling Stock Manufacturing Industry Association (1932). Juji Kii became president of Kinki Sharyo (Rolling Stock) Company, Ltd. (1947).