Hydrocarbon synthesis from biomass-derived syngas (bio-syngas) has been investigated as a potential way to use biomass. The FischerTropsch reaction has been carried out using CO/CO2/H-2/Ar (11/32/52/5 vol.%) mixture as a model for bio-syngas on co-precipitated Fe/Cu/K, Fe/Cu/Si/K and Fe/Cu/Al/K catalysts in a fixed bed reactor. The reaction with the model bio-syngas showed that only CO was converted to hydrocarbons while. in the reaction with a balanced (i.e. H-2-enriched) feed gas, CO2 was converted to hydrocarbons as well as CO. In the optimization of the catalyst composition that employed bio-syngas, alumina as a structural promoter gave much higher activity for hydrocarbon production than silica. K addition promoted the catalytic activity and the selectivities toward olefins and long-chain hydrocarbons, but too high K promotion caused the gradual deactivation of the catalysts. Some performances of the catalysts that depended on the syngas composition are also presented. (C) 2003 Elsevier B.V. All rights reserved.