Abstract: A process for upgrading a nitrogen and sulfur rich heavy naphtha feedstock includes the steps of providing a naphtha feedstock having an initial nitrogen content, an initial sulfur content and an initial octane number; contacting the naphtha feedstock with an acid source so as to provide a reduced nitrogen feedstock having a reduced nitrogen content which is less than the initial nitrogen content; contacting the reduced nitrogen feedstock with a hydroconversion catalyst system under a hydrogen atmosphere, temperature and pressure so as to provide a final product having a final nitrogen content which is less than the initial nitrogen content, a final sulfur content which is less than the initial sulfur content, and having a final octane number which is substantially equal to or greater than the initial octane number of the feedstock, and wherein the final product has an increased isomerized component and substantially no increase in aromatic content with respect to the feedstock.