Abstract: A process for the preparation of a catalyst which is highly active for the synthesis of hydrocarbons from mixtures of hydrogen and carbon monoxide. A silica or silica-containing support is treated with a solution containing both an Iron Group metal, or metals, and nitrous acid, nitric acid, or a nitro-containing organo, or nitro-containing hydrocarbyl compound, or compounds, sufficient to hydroxylate the surface thereof and increase the number of hydroxyl groups on the surface of the support such that the metal component will be highly dispersed, this increasing the activity of the catalyst in a hydrocarbon synthesis reaction as contrasted with that of a catalyst of similar composition, similarly prepared except that the support component of the catalyst was not contacted and simultaneously treated with both the Iron Group metal and the acid.