The multiple zeolite catalyst is a catalytic composition used to convert C9+ alkylaromatic hydrocarbons to BTX, particularly commercially valuable xylenes. The catalyst is formed by mixing at least two zeolites selected from mordenite, beta zeolite, ZSM-5, ZSM-11, ZSM-12, ZSM-22, ZSM-23, MFI topology zeolite, NES topology zeolite, EU-1, MAPO-36, SAPO-5, SAPO-11, SAPO-34, and SAPO-41, and adding at least one metal component selected from Group VIB and Group VIII of the Periodic Table of the Elements. The two zeolites should have different physical and chemical characteristics, such as pore size and acidity. An exemplary catalyst includes mordenite, ZSM-5, and 3 wt. % molybdenum. The transalkylation reaction may be conducted in one or more reactors with a fixed bed, moving bed, or radial flow reactor at 200-540° C., a pressure of 1.0-5.0 MPa, and liquid hourly space velocity of 1.0-5.0 per hour.