HYDROGEN GENERATOR AND FUEL CELL SYSTEM

A hydrogen generator (1) includes: a tubular reformer (2) configured to generate a hydrogen-containing gas by a reforming reaction using a material gas; a CO reducer (4) configured to reduce carbon monoxide contained in the hydrogen-containing gas generated in the reformer; a tubular hydro-desulfurizer (3) provided at an outer periphery of the reformer and configured to remove a sulfur compound contained in the material gas; and a material gas supply passage(331) through which the material gas to be supplied to the hydro-desulfurizer flows. The material gas supply passage is configured to perform heat exchange with the CO reducer, and a material gas inlet port (341) of the hydro-desulfurizer is provided at an end surface closer to the CO reducer.