Abstract: Internal friction and relative dynamic modulus in the oilquenched Ni-36Al, Ni-27Al-12Fe, Ni-21.2Al20Fe and Ni-24Al-16Fe were measured using a multifunctional internal friction apparatus from room temperature to 400 °C. It was suggested that the internal friction peak is resulted from reverse martensitic transformation of L10→γ during heating. The peak temperature is decreased when Fe content is increased and is also correlated with Aleq. The oilquenched Ni-21.2Al20Fe has the largest peak height, the narrowest peak width and the lowest peak temperature, while the oilquenched Ni-36Al alloy has the smallest peak height, the widest peak width and the highest peak temperature among the four alloys. The XRD results show that the oilquenched Ni36Al alloy possesses almost complete martensitic structures, while the oilquenched Ni-21.2Al-20Fe contains the intermetallic compounds such as Ni3Al and Ni5Al3 in addition to martensite. The internal friction peak height is related to the transformation amount per unit time and the total transformation amount is also related with transforming time that is determined by peak width.