A process for preparing a catalyst composition comprising (a) preparing a carrier comprising (i) mordenite in an amount in the range of from 20 to 80 wt %, based on total weight of carrier, (ii) ZSM-5 type zeolite in an amount in the range of from 10 to 70 wt %, based on total weight of carrier; and (iii) an inorganic binder in an amount in the range of from 10 to 50 wt %, based on total weight of carrier; (b) incorporating in the carrier molybdenum in an amount in the range of from 1 to 10 wt %, as metal based on total weight of catalyst composition, and subjecting the thus treated carrier to a temperature of from 100 to at most 300° C. and (c) incorporating in the molybdenum containing carrier obtained in step (b) platinum in an amount of from 0.005 to 1 wt %, as metal based on total weight of catalyst composition, and subjecting the thus treated carrier to a temperature of from 200 to at most 600° C.; and a process for conversion of alkylaromatic hydrocarbons containing feedstock using a catalyst prepared by said process. Process using the prepared catalyst composition for alkylaromatic hydrocarbon conversion.