With the aid of ANSYS software,the overall model of the cryogenic storage tank was worked out for nonlinear analysis of the structure during vacuumizing with outside heating. It is found that the temperature difference between the inner vessel and out shell during outside heating will induce plastic deformations at the strips,which would damage the connect strength of the strips in transporting. An improved method was suggested to reduce the plastic deformation of the strips by heating the cryogenic storage tank inside and outside at the same time. And the proposed method was verified by finite element numerical simulation.