Conventional (per)sulfated bulk zirconia, mesoporous sulfated zirconia and (per)sulfated zirconia supported on an ordered mesoporous silica, with or without aluminium incorporation, were examined as acid catalysts for the dehydrocyclisation of xylose into furfural. Furfural yields of up to 50% could be achieved at > 90% conversion with the modified zirconia catalysts, which is better than that achievable with H2SO4 (using approximately the same equivalent amount of sulfur.)