The effect of pouring temperature on microstructure and bonding properties of the Mg/aluminised steel bimetallic castings prepared by the solid–liquid compound casting process was investigated in this paper in order to improve the interface bonding of the Mg/aluminised steel bimetallic castings. The results show that the Mg/aluminised steel bimetallic castings produced with different pouring temperatures obtained a uniform interface layer that was mainly composed of the Fe2Al5, τ10-Al9Fe4Si3, FeAl3 and Al12Mg17 phases. When the pouring temperature was low, the cracks were formed between the Mg and the interface layer. With increasing pouring temperature, a compact interface bonding was achieved. The bonding properties of the Mg/aluminised steel bimetallic castings increased with increasing pouring temperature. An optimised bonding of the Mg/aluminised steel bimetallic castings was obtained with a pouring temperature of 780°C. [ABSTRACT FROM AUTHOR]