A series of Ni/SBA-15 catalysts with Ni contents from 7.5 wt% to 15 wt% were prepared by impregnation method. The effect of O2 and H2O on the combined reforming of the simulated biogas to syngas was investigated in a continuous flow fixed-bed micro-reactor. The stability of the catalyst was tested at 800℃. The results indicated that 10wt%Ni/SBA-15 catalyst exhibited the highest catalytic activities for the combined reforming of the simulated biogas to syngas. Under the reaction conditions of the feed gas molar ratios CH4/CO2/O2/H2O= 2/1/0.6/0.6, and the yields of CO and H2 were 99.0% and 82.0%, respectively. The catalytic activities of the catalyst did not decrease obviously after 100 h reaction time on stream.