The fabrication and modification of metal zeolite catalysts for the conversion of heavy aromatics were investigated. The catalytic performances for various metal-free 12-MR zeolites were evaluated in terms of conversion, product yields, benzene purity and reaction network analyses using transalkylation of toluene and 1,3,5-trimethylbenzene as the test reaction. The effects of metal content, feed impurity, and steaming treatment on the catalytic performances of Pt/mordenite zeolites prepared by different metal incorporation methods were also examined. A sulfuration technique for fine tuning the catalytic activity of the metal catalyst while sustaining desirable stability and performance was developed and its application for transalkylation of heavy aromatics was illustrated by Pt/ZSM-12 catalyst.