Prototype 5 kW-class fuel processor based on steam reforming of natural gas with heat and system integration has been designed and fabricated for use in proton exchange membrane(PEM) fuel cell with residential applications. Endothermic heat for steam reforming has been supplied by radiation type metal fiber burner. The performance of the integrated system has been experimentally evaluated for the reformer temperature of 600-800 ℃ at constant GHSV of each reactor and atmospheric system pressure. The final product(β+ type) can produce the total gas flow of 6.5 Nm(3)/h(H2 conc.: 74%, dry basis) under reformer temperature and space velocities of 800 ℃, 1,950 h(-1), respectively and also remove CO concentration under 10 ppm by two series fin type packed beds employing Pt[λ(2O2/CO)=2.1] and Ru[λ(2O2/CO)=3.5] catalysts with interstage cooling. The overall fuel processing efficiency of about 52% calculated by the ratio of total H2 output after PrOx to total methane flow into the reformer and the burner based upon higher heating values is somewhat lower. This was mainly attributed from the fact that heat loss from the exhaust gas after supplying heat necessary for raising the reformer temperature by combustion of natural gas was excessively high.