The strain characteristics and deformation environment of Gongcheng—Limu fault zone were discussed based on the finite strain analysis and differential stress estimation in this paper.The analysis results indicate:①The change scope of Flinn parameters（K） is between 0.32 and 1.67;the average strain principal axis is 276°∠21°which is consistent with the whole thrust direction of the fault zone;the average strain degree of the fault zone ranges from 2.26 to 3.00;The strain type of the fault zone is a superimposi-tion style composing of flattening strain and plane strain of simple shear.②The differential stress value is 40-80 MPa.The deformation depth of the fault zone is less than 10km and belongs to the half brittleness-half toughness deformation domain.③The strain characteristics coincides with deformation environment and macroscopically structural style of the fault zone.