Abstract: Aiming at the problem that complex contours in 3D printing of aerospace metal components are prone to errors and incomplete filling, a laser zonal scanning method for 3D printing of aerospace metal components based on contour data curve interpolation is proposed. MS (contour extraction algorithm) is used to obtain the binary image contour of the component, NURBS (non-uniform rational B-spline interpolation) algorithm is used to fit the contour by adjusting the weighting factor and control points to obtain the smooth curve, calculate the minimum enclosing box of the smooth contour, and determine the optimal square edge length based on the constraints of the residual stress, molding efficiency and accuracy to complete the square mesh partitioning, and then the zigzag (zig-zag) is used to partition the square mesh in the partition. The square mesh partitions are completed, and zigzag lines are used in each partition for scanning, and the scanning paths of neighboring partitions are connected to each other at the beginning and the end. The experimental results show that NURBS interpolation significantly reduces the contour error, and the square partitioning combined with zigzag scanning ensures the scanning paths are tight and filled completely, which effectively improves the 3D printing quality of aerospace metal components.