The accuracy of DC electronic voltage transformer is related to the accurate measurement of power in DC transmission system. At present, the accuracy of DC electronic voltage transformer exists in practical operation, but there is little research on measurement error of DC electronic voltage transformer. Therefore, this paper establishes error model for each link of DC electronic voltage transformer, analyses the error of transformer body, A/D conversion error of remote module and interpolation error of merging unit, and gives the range of theoretical error of each part. It is concluded that the error of DC electronic voltage transformer mainly comes from the transformer body. Finally, the error test of transformer is carried out, and the experimental results are basically consistent with the theoretical error range.