The invention discloses a model updating method based on strain modal shape correlation. The specific steps are as follows: step 1), establishing a finite element model of a structure and analyzing the finite element model; step 2), performing experimental design and analysis; step 3), extracting a finite element simulation strain mode; step 4), performing correlation analysis: adopting a model confidence factor, and analyzing the correlation between the finite element model and the strain modal shape of an experimental test; step 5), selecting a mode to be modified; step 6), selecting a parameter to be identified; step 7), constructing a modification target; and step 8), performing modified iteration. According to the model updating method based on the strain modal shape correlation provided by the invention, by selecting an appropriate unit type, the obtained finite element model of the structure provides a reference model for strain response calculation; by selecting an appropriate strain mode to be modified, parameters to be modified and an optimum design method, the modified finite element model can better reflect the strain response of the structure; and the accurate finite element model is beneficial to the subsequent structural dynamic optimization design based on the finite element model, and the development of structural health monitoring and structural response prediction and so on.