Abstract: The boundary layer is a thin layer close to the object surface in fluid motion, and high-quality boundary layer grids are the basis for obtaining accurate results in aircraft fluid dynamics calculations. In response to this issue, this paper proposes a high-quality unstructured construction method for boundary layer mesh generation. Based on surface mesh hyperplane segmentation, first select support points for each segmentation and calculate support lines, according to the lifting of support lines and segmentation boundary lines, contour lines are obtained, and the support lines and contour lines form a framework line. Then, based on the interpolation of the framework line, generate a segmented unstructured boundary layer top surface mesh. Further collision detection and processing of the top mesh of the unstructured boundary layer. Finally, an unstructured boundary layer mesh is generated through internal interpolation. The experimental results compared with the mainstream advancing layer method show that according to relevant quality evaluation standards, the unstructured boundary layer mesh generated by the proposed method has no folding elements, and the average reduction of low-quality elements is 15%.