Natural gas fuel processor has been developed for 1 kW class residential PEMFCs system. Unit processes and auxiliary units are integrated into packaged hardware, which shows thermal efficiency of 78% as a HHV basis with methane conversion of 92% at rated load. After confirming the performance at rated load, partial load operations are carried out by investigating the composition of product gas and thermal efficiencies at discrete load levels. The start up tine is about an hour for CO concentration in product gas below 10 ppm. Dynamic response of fuel processor with load fluctuation is investigated to establish the load change strategy. In the following paper, operation results of fuel processor as well as fuel, processor failure analysis are presented to evaluate the develop sd fuel processor.