The rotary extrusion process provides a possible new way for forming Nibased Fe-based shape-memory alloy composite pipes. However, due to the large differences in strength and plasticity between the two materials, during the forming process, the deformation is not harmonious and non-uniform,which leads to the problems of large flow velocity difference and delamination at the composite pipe interface. For this reason, this paper designed three deformation modes, the effects of billet temperature, extrusion ratio and die angle on the flow velocity difference and radial compressive stress were studied by finite element simulation. It is found that the differences of interfacial flow velocity under the three deformation modes increase with the increase of billet temperature, extrusion ratio and die angle; with the decrease of billet temperature and the increase of extrusion ratio, the radial compressive stresses increase; with the increase of die angle, the radial compressive stresses under the internal fixing and external reduction mode and the internal expansion and external reduction mode show a decreasing trend, however, the radial compressive stress under the overall reduction mode shows an increasing trend. Then the reasonable deformation mode of the rotary extrusion is determined: the internal expansion and external reduction mode.