Isomerisation of nC7 over a sulphated zirconia (SZ)-based bifunctional catalyst was studied at 150 • C. Au, Ir, Pd and Pt were used as promoters of SZ. The first objective was the production of C7 isomers with high octane numbers. PtSZ is the most suitable catalyst despite low conversions and a high proportion of methylhexanes instead of dimethylpentanes. The second objective was to assess Au as a promoter of SZ. Au shows slight hydrogenation abilities, displaying behaviour similar to that of Pd, but is inactive towards alkane activation. These promising but inadequate results suggested that Au could be used as the metallic function of bifunctional catalysts if the support were judiciously chosen and the preparation method optimised.