A process for the oxidation of hydrocarbons comprises contacting the hydrocarbon with an oxygen-containing gas in the presence of a catalyst comprising a microporous solid support, preferably a zeolite, having from 8- to 12-ring open windows and comprising non-framework metal cations selected from manganese, iron, cobalt, vanadium, chromium, copper, nickel, and ruthenium, and mixtures thereof, providing that the oxygen-containing gas does not contain significant amounts of added hydrogen. The catalyst is novel and forms part of the invention.The process may be used for oxidation of alkanes, cycloalkanes, benzene and alkylbenzenes, and is suitable for use in regioselective terminal oxidation of straight chain alkanes and for selective oxidation/separation of p-dialkylbenzenes from an alkylbenzene mixture, for example, p-xylene from an isomeric mixture of xylenes.