A new preparation route for low valent and well-dispersed tungsten species supported on alumina was investigated. Tungsten hexacarbonyl was deposited on partially hydroxylated gamma-alumina by gas phase adsorption in a fluidized bed reactor. The increase of metal loading during deposition and decarbonylation cycles was studied. A clear equilibrium was achieved in longer periods of continuous deposition. With a pulse technique growth in the tungsten loading was linear. A partial decarbonylation cycle between the pulses could prove to be of some value in the preparation of certain catalyst.