Abstract: The supported NiO-Fe₂O₃/modified dolomite (NiO-Fe₂O₃/MD) catalysts were prepared by deposition-precipitation (DP)method using modified dolomite as carrier, and different approaches including XRD, SEM, TEM and BET were used to characterize the synthetic catalysts. Meanwhile, the catalytic gasification of municipal solid wastes (MSW) was conducted to test the catalytic activity and life of NiO-Fe₂O₃/MD catalyst in a bench-scale combined fixed bed reactor, and compared with the catalytic properties of NiO/MD catalysts. The results indicated that the prepared NiO-Fe₂O₃/MD catalysts had a coated core-shell structure, the particles size of the active components in catalyst surface were about 37 nm, and they had also a high BET surface area of 62.48 m²/g. The catalytic activity testing showed that the NiO-Fe₂O₃/MD catalysts using in gasification of MSW had a very high catalytic activity, which could significantly improve the quality and H₂ yields of the produced gas, meanwhile efficiently eliminate the tar generation. Comparing with NiO/MD catalyst, the NiO-Fe₂O₃/MD catalyst demonstrated its unique property in preventing deactivation to attain a longer lifetime.