With naphthalene as biomass tar model compound, partial oxidation reforming (with addition of O2) and dry reforming of biomass fuel gas were investigated over nickel-based monoliths at the same conditions. The results showed that both processes had excellent performance in upgrading biomass raw fuel gas. Above 99% of naphthalene was converted into synthesis gases (H2+CO). About 2.8 wt% of coke deposition was detected on the catalyst surface for dry reforming process at 750 oC during 108 h lifetime test. However, no coke deposition was detected for partial oxidation reforming process, which indicated that addition of O2 can effectively prohibit the coke formation. O2 can also increase the CH4 conversion and H2/CO ratio of the producer gas. The average conversion of CH4 in dry and partial oxidation reforming process was 92% and 95%, respectively. The average H2/CO ratio increased from 0.95 to 1.1 with the addition of O2, which was suitable to be used as synthesis gas for dimethyl ether (DME) synthesis.