The diamond wire-sawing process was developed to cut granite in both quarries and block processing plants. In this paper, swarf was collected from different areas along the sawing arc when sawing three granites. The particle size distribution and the morphology of the swarf were investigated systematically, along with the swarf formation mechanism in sawing. Granite swarf formation was dominated by transgranular fractures based on the morphology of sawn granite chips and the analysis of sawn chip size. A long cutting arc increased the movement among the swarf, tool, and workpiece, thereby inducing a secondary fracture in the sawn chip.