The objective of this work is to analyze the performance of a composite palladium-based membrane reactor (MR) by performing the natural gas steam reforming reaction at low operating conditions for producing high purity hydrogen. The MR comprises a composite membrane, having similar to 13 mu m Pd layer deposited on a porous stainless steel support, fabricated via electroless plating and a commercial Ni-based catalyst. The composite membrane shows infinite ideal selectivity, H-2/He and H-2/Ar, at trans-membrane pressures less than 100 kPa and T=400 degrees C at the onset of experimental testing. The steam reforming reaction is performed at 400 degrees C, by varying the reaction pressures and sweep gas flow rate between 150 kPa and 300 kPa, and 0100 mL/min, respectively. The gas hourly space velocity (GHSV) and steam-to-carbon ratio (S/C) are kept constant at 2600 h(-1) and 3.5. The effect of CO2 as an impurity in the feed line is also analyzed at 400 degrees C and 150 kPa. The best performance of the Pd-based MR is obtained at 400 degrees C, 300 kPa and 100 mL/min of sweep-gas, yielding a methane conversion of 84%, hydrogen recovery of 82%, and obtaining a pure hydrogen stream at the permeate side. The Pd/PSS MR worked for more than 700 h under differing operating conditions. As a comparison, a conventional reactor operating at the same MR conditions is compared and discussed.