The reverse transformation behavior was investigated by DSC analysis in thermomechanically processed Fe-30%Ni-0.35%C alloy. Upon increasing the heating rate from $5^{circ}C/min$ to $80^{circ}C/min$, the As point of the ausformed martensite was not changed and the As point of the marformed martensite decreased at reverse transformation. The Af points showed to be constant with increasing the heating rate both in the ausformed martensite and in the marformed martensite. With increasing the deformation degree, the As points of the ausformed martensite and the marformed martensite increased and the Af points appeared to be constant, structures. The enthalpy changes increased with increasing the heating rate, but decreased with increasing the deformation degree in both structures.