Abstract: Al-Ni hypoeutectic/eutectic alloys has both high strength, toughness and high thermal conductivity.The eute-ctic composition point of Ni in Al is higher than that of the other common transition group elements.Its castings have considerable application potential in the field of thermal management materials.The effects of adding a small amount of Fe on the microstructure, thermal conductivity/mechanical properties and rheological behavior of Al-5wt%Ni alloys were explored.The results show that the addition of 0.1wt% Fe in Al-5wt%Ni could result in significant refinement of α-Al grains, (α-Al+Al₃Ni) eutectic structure spheroidization and the second phase distribution is more uniform.When the Fe element is added at 0.1wt%, the thermal conductivity and mechanical properties of Al-5wt%Ni alloy improve simultaneously, the thermal conductivity increases from 211.4 W/(m·K)to 218.8 W/(m·K), the tensile strength increases from 132.5 MPa to 170.9 MPa.The rheological behavior of the alloy melt is characterized by the high-temperature melt couette viscometer, and it is found that the addition of 0.5wt%Fe element in the Al-5wt%Ni alloy cause the viscosity of the liquid melt to increase, but the shear thinning effect of the melt is more prominent at 645 ℃.