Uptake of fructose by intact cells of Haloferax volcanii, one of the sugar-utilizing halobacteria, was examined with the following results. (i) The fructose transporter was inducible, (ii) Kinetic analysis showed a Ktof 0.37 μM and a Vmaxof 4.61 nmol∙mg protein−1∙min−1. For a glucose transport system in this bacterium, Ktwas 12.5 μM, showing that the fructose transporter had a much larger affinity for a substrate than the glucose transporter, (iii) No uptake was observed by the envelope vesicles, (iv) Phloridzin and phloretin inhibited fructose transport, although a relatively higher concentration was required than that needed to inhibit glucose uptake, (v) The driving force for fructose transport was a Na+electrochemical potential gradient, (vi) Glucose and fructose were interchangeable and this conversion led to the expression of the glucose transporter even when fructose was used as the sole carbohydrate, and vice versa.Key words: glucose uptake, symport with Na+, phloridzin, phloretin, Haloferax volcanii.