A phase transformation behavior under the force driven of shape memory alloy was described by the phase transition surface constructed by the VonMises equivalent stress surface.By using the implicit stress integration,a constitutive model considering phase transformation behavior of superelastic NiTi memory alloys was established based on the generalized plastic theory,which was verified by experiments.The results show that the model can describe stress induced martensitic transformation with the temperature dependent,and also can give a reasonable description of the behavior of Martensite and its reverse phase transformation.