There is proposed a method for pre-reforming a hydrocarbonaceous feed stream into a pre-reforming product containing carbon oxides, hydrogen and hydrocarbons, in which the adiabatically operated pre-reforming reactor comprises at least two reaction zones designed as fixed beds in a common reactor vessel, which are in fluid connection with each other and are filled with beds of granular, nickel-containing catalyst active for pre-reforming, wherein the first reaction zone in flow direction is filled with a catalyst active for high-temperature pre-reforming and the last reaction zone in flow direction is filled with a catalyst active for low-temperature pre-reforming.