In the present study, the effects of preactivation stage and graphite content on the reduction and synthesis mechanisms of ZrO2-NiO-Mg-graphite system were evaluated. For this purpose, the powder mixture with stoichiometric ratio was exposed to milling process. After the combustion it was found that the synthesis did not occur completely. By adding 10 wt% Mg to the mixture and further milling, the synthesis was completed and NiZr intermetallic compound was formed. Preactivation stage was carried out to complete the synthesis and reduction process of the composite samples. It was determined that after 6 h of preactivation, combustion time increased due to increase of oxide particles surface area and presence of graphite as a barrier between Mg and oxide particles. To confirm this, the mechanochemical process was performed with different graphite contents. It was realized that by increasing the graphite content as a postponing agent to levels higher than the stoichiometric limit, the synthesis was completed after 1200 min of milling without the presence of intermetallic compound.