A process for converting hydrocarbons into aromatic compounds, which entails contacting a composition containing hydrocarbons with a catalyst under temperature and pressure conditions to produce the aromatic compounds, the catalyst containing a matrix of .eta. transition alumina and/or .gamma. transition alumina. The catalyst contains 0.001 to 2 wt % of silicon, 0.1 to 15 wt % of at least one platinum group metal, and 0.005 to 10 wt % of at least one promoter metal. The promoter metals may be tin, germanium, indium, gallium, thallium, antimony, lead, rhenium, manganese, chromium, molybdenium or tungsten. The catalyst may also contain a doping metal.