Objective The orthopedic device is inevitable to deform during wearing, resulting in error in the output of corrective force. To ensure the accuracy of the force model, it is necessary to obtain the three-dimensional shape information of the orthopedic device, thus this paper explores a method suitable for three-dimensional surface shape reconstruction of orthoses. Method The distribution of curvature along the arc length is obtained through interpolation based on the local curvature on the surface, then the contour curves are reconstructed according to the Frenet frame theory, and finally, several contour curves are integrated to achieve surface reconstruction. Results The maximum distance error and shape reconstruction error of the 50 cm overall contour curve reconstructed using nearest neighbor interpolation and cubic spline interpolation are both less than 1.303 cm and 0.963 cm. The reconstructed surfaces maintain the shape features of the reference surface, with mean absolute error and root mean square errors less than 0.770 cm and 0.860 cm. The overall performance of spline interpolation method is slightly better than nearest neighbor interpolation. Conclusions The proposed method for reconstructing the three-dimensional shape of orthoses is effective and reliable, meanwhile is applicable for orthoses with complex shapes.