Biogas is a typical renewable bio-energy derived from anaerobic digestion process, mainly composed of methane and carbon dioxide. Dry reforming is a promising technology which can utilize biogas and produce syngas. In this study, Ni catalysts using different supports were synthesized and characterized systematically via N2-physisorption, XRD, TEM, EDS, XPS, H2-TPR and TGA. The catalytic activity and stability of different catalysts was investigated under 600-850 ?. It was found that the Ni/MgO catalyst is a promising catalytic material which showed both good activity and stability due to the strong interaction between Ni and support. Besides, as impurities like H2S, O2 and N2 exist in biogas; they cannot be ignored during biogas dry reforming. Therefore the effect of H2S in different concentrations on biogas reforming was also focused on. Experimental results based on Ni/MgO catalyst as well as a review of recent studies concerning impurity effects are shown, suggesting that impurities even in trace amount can affect the performance of reforming. This research provides a useful reference for industrial operation of biogas dry reforming.