The flanging performance of 6061 aluminum alloy round hole was studied by ordinary incremental forming technology. Then, the influence laws of multi-pass incremental forming with different prefabricated hole diameters and different forming paths on the flange height and wall thickness distributions of 6061 aluminum alloy were investigated, and the method of obtaining the limit flanging parts 6061 aluminum alloy was discussed. The experimental results show that the forming performance of sheet in single-pass incremental forming is poor, and there is a thinning band in the middle, but the flanging coefficient is still higher than that of ordinary incremental forming. Therefore, the forming performance is optimized by designing multi-pass incremental forming reasonably. Among the three schemes, the flanging path in variable height incremental forming obtains larger parts compared with the flanging paths in variable angle incremental forming and single-pass incremental forming, and compared with the other two paths, the flanging path in variable angle incremental forming avoids excessive thinning of wall thickness to obtain the parts with relatively uniform wall thickness. However, compared with two-pass and single-pass incremental forming, the quality of flanging parts obtained by three-pass incremental forming is better.