Hot compression tests of a new CrMoV alloy for piston ring are conducted by Gleeble-3800 thermal mechanical simulationtester at the temperature of 950, 1000, 1050, 1100 and 1150 °C and strain rate of 0.01, 0.1, 1, 10 s−1. The results show thatthe true stress strain curves first go up to peak, and then go down to steady state in accord with characteristics of dynamicrecrystallization, indicating that the main softening mechanism of this alloy during hot deformation is dynamic recrystallization. The hot deformation behavior of this alloy is characterized by Arrhenius hyperbolic sine relationship with theactivation energy and stress index. On the basis of the true stress strain curves, the constitutive equation of the peak flowstress of this alloy is established. With the equation, the flow stress of this alloy can be predicated by numerical simulationfor a new type piston ring.