The invention relates to the field of electrical cabinets, in particular to a nine-fold section material cabinet decorating plate assembly and a nine-fold section material cabinet. The nine-fold section material cabinet decorating plate assembly comprises a decorating plate. Lug plates used for being fixedly matched with tee connecting parts of the cabinet are arranged at the two ends of the decorating plate respectively. Connecting holes used for being matched with the corresponding tee connecting parts are formed in the lug plates. In addition, reinforcing supporting strips are fixedly assembled at the inner side of the decorating plate and provided with fixing holes used for being fixedly connected with a framework of the cabinet. On the premise of ensuring that the decorating plate is assembled reliably and does not deform, the problem that the decorating plate of the cabinet and a hoisting beam can not exist together is solved.