Abstract: The morphology of metal powder used for 3D printing was observed by scanning electron microscopy backscattered electron mode, and its sphericity was analyzed by image analysis software. The results show that when the image analysis software was used to identify the metal powder images for 3D printing, the scanning electron microscopy backscattered electron mode image was better than the secondary electron mode image. For 3D printing metal powder with poor particle shape, it can be manually separated after the image analysis software automatic identification the image particles, so as to improve the analysis accuracy of metal powder sphericity.