Abstract: The present invention belongs to the precise and efficient processing field of micro parts, in particular to a deformation prediction method of micro-milling thin-walled parts. Firstly, based on the finite element simulation software, a finite element simulation model of micro-milling thin-walled parts is established. Johnson-Cook material model and failure criterion are used to describe the material properties and damage criteria of the machined materials, so as to realize the prediction of milling force in the micro-milling process. The accuracy of the model is verified by experiments. Then, based on the birth-death element method, a deformation prediction model of micro-milling thin-walled parts model is established, and the milling force output from the finite element simulation model is loaded into the deformation prediction model. Finally, the deformation prediction of d micro-milling thin-walled parts is realized.