HYDROGEN GENERATION APPARATUS, METHOD FOR OPERATING SAME, AND FUEL CELL SYSTEM

A hydrogen generating apparatus includes: hydrodesulfurizer (2) for reducing a concentration of a sulfur compound contained in raw material fed from a raw material feed path; reformer (1) for reforming the raw material discharged from hydrodesulfurizer (2) to generate hydrogen-containing gas; and recycled gas flow path (3) for feeding a part of the hydrogen-containing gas discharged from reformer (1) to the raw material feed path. The hydrogen generating apparatus further includes: ejector (4) provided at a junction of the raw material feed path and recycled gas flow path (3), and configured to draw the hydrogen-containing gas from recycled gas flow path (3) into the raw material feed path; and valve (5) provided in recycled gas flow path (3) to close when the raw material flowing into the ejector (4) is not larger than a predetermined flow rate. In this way, it is possible to achieve hydrogen generating apparatus (100) in which backflow in recycled gas flow path (3) is prevented.