Abstract: A Chromium-doped mesoporous zirconia molecular sieve was directly synthesized using zirconium nitrate hydrate and chromium chloride hexahydrate and then impregnated in H2SO4 solution to make a super acid solid catalyst. XRD and NH3-TPD were adopted to characterize the phase and superficial acidity of the as-synthesized sieve and catalyst. The influence of the addition of triethanolamine and chromium on synthesised products was studied in detail. The isomerization of n-pentane was used to evaluate the catalytic activities of the as-synthesized super acid samples. It is found that the addition of chromium is helpful to the thermal stability of mesoporous zirconia because the possibility that the quadratic crystal of the zirconia transforms to monoclinic phase reduces and that the addition of triethanolamine increases the order degree of the Cr mesoporous zirconia and the dispersion of chromium. The isomerisation results show that with chromium incorporation the acid sites and acid intensity of the mesoporus zirconia are increased, resulting in stable pentane conversion and isopentane selectivity. The selectivity and yield of i-pentane are 40 % and 10 %, respectively.