This study is to suggest some ideas for improvements of classification and expansion of the arts in the KDC. In order to this study, analysed changes of terminology, auxiliary tables and notes, and expansion of classification number of the arts from 1st edition to 5th edition of the KDC. The arts of KDC did not changed from 1st to 3rd edition and changed in the 4th edition and 5th edition, and errors and problems of previous edition were not improved, and Classification number and expansion of KDC found out poor rather than different classification schedule because had a lot of Including notes. The result of analysis proposed to improved method to solve the problems.