Abstract: To meet the alignment requirement of superconducting radio frequency (SRF) cavity and superconducting magnet at cryogenic temperature in the accelerator system, the design of adjustment and alignment of the cold mass in superfluid helium cryomodule should be analyzed. The cryogenic deformation of the cold mass at the 2 K superfluid helium temperature level was simulated and obtained by the finite element method, meanwhile the simulation analysis method was checked by the cryogenic deformation data of the cold mass online measured by the wire of position monitor (WPM). The results show that the simulation result and measurement result have a good consistency, and it provides an important data foundation for the alignment design in the type of bottom supported cryomodule.