Method for isomerizing halogenated aromatics

The present invention relates to a catalyst composition and a method for isomerizing halogenated aromatics. Particularly, the present invention relates to a catalyst and a method for isomerizing halogenated aromatics such as dichlorobenzene (DCB), chlorotoluene (CT) or dichlorotoluene (DCT), etc., for increasing m-DCB, m-CT, 2,6-DCT or 3,5-DCT. A catalyst composition with a high halogenated aromatics isomerization activity, a halogenated aromatic isomerization method using said catalyst composition, and a halogenated aromatics isomerization method capable of prolonging the life or regeneration period of the catalyst. The invention also includes a catalyst composition characterized in that the maximum diameter of secondary particles of the zeolite in the formed catalyst is 5 microns or less is used to improve the halogenated aromatics isomerization activity. Furthermore, if dissolved oxygen is decreased, the life or regeneration period of the catalyst can be prolonged.