Using the ternary microscopic phase-field model, the effect of Fe content on antisite defects NiAl and AlNi in two types of NiAlFe ternary alloys were simulated and calculated; one type is the NiAlFe alloy with Al content larger than 25%, and the other type is the NiAlFe alloy with Ni content larger than 75%. NiAl (AlNi) stands for the antisite defect which is caused by Ni(Al) atoms occupying Al(Ni) sites. The results show that, in a certain temperature range, with more Fe added, in NiAlFe alloys with Al content larger than 25% the AlNi concentration increases obviously, while the NiAl concentration increases slightly whose values are smaller than AlNi concentration; on the contrary, in NiAlFe alloys with Ni content larger than 75% the NiAl concentration increases obviously and its values are larger than AlNi concentration; at the same temperature, we made a comparison between the NiAlFe alloys with Al content larger than 25% and the NiAlFe alloys with Ni content larger than 75% to study the influence of Fe content on antisite defects in these two types of alloys, and found that AlNi concentration in the former alloys is more easier to be affected by Fe content than in the latter alloys, while NiAl concentration in the latter alloys is more easier to be affected by Fe content than in the former alloys. Besides, the concentrations of NiAl and AlNi change with timesteps gradually from an initial value to the equilibrium value; elevating the temperature causes the evolution process of antisite defects to turn slower and the equilibrium values become lager