This paper investigates the characteristic important to metal injection moulding (MIM) process via rheological behavior of MIM feedstock. A gas atomized spherical ZK60 magnesium (Mg) alloy powder and the binder of 60wt.% palm stearin (PS) + 40wt.% low density polyethylene (LDPE) were used in this investigation. Prior to mixing process, critical powder volume percentage (CPVP) was determined and subsequently four different feedstocks with powder loading of 62, 64, 66 and 68vol.% were prepared. The properties of the feedstocks were then analyzed rheologically. Here, the flow behavior index n, the flow activation energy E and the mold ability index αSTV of the Mg alloy MIM feedstocks were determined. Results show that feedstock with 64% powder loading has the best rheological properties and therefore it is considered to be the best for the injection moulding process.