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A novel concept of stepped superplasticity deformation (Stepped-SPD) was proposed for exploring a way from superplasticity deformation process to enhance the metal plasticity. In that Stepped-SPD process, the constant speed deformation and the maximum m superplasticity deformation ( Max m SPD) were adopted superlatively to finish the tension of samples through two steps. The strain of the first step and clearance time between two steps in Stepped-SPD were controlled in order to facilitate the grain refinement and structure improvement which induced plasticity enhancement. In these experiments, stepped tension deformation was compared with single-step tensile deformation and the influences of pre-strain of the first step in Stepped-SPD on elongation and microstructure were analyzed. The results for TC6 alloy without grain refinement treating show that the Stepped-SPD tensile method obtains the best SPD capability, with an elongation of 2053% corresponding to the pre-strain of 2.0, whereas the Max m SPD and constant speed tensile method produces the biggest elongations of 1347% and 753.9%, respectively. The elongation for TC4 titanium alloy using stepped tensile test is 2147% corresponding to the pre-strain of 1.5 in the first deformation step. Thus, it is indicated that the Stepped-SPD induces the plastic enhancement in comparison with the single-step deformation. Moreover, the pre-strain determines the grain size of the tensile sample in Stepped-SPD.