Abstract: Batch fracture reasons of a batch of toothed plate of cable cutters were analyzed by macro examination, metallographic examination, hardness testing, chemical compositions analysis, SEM observation and XRD analysis. The results show that high temper brittleness and heavy shrinkage porosity in fine casting were the main reasons for the fracture, and non-metallic inclusions, phosphorus eutectic structure and Fe-Cr-Mn compound caused by elements segregation accelerated the fracture. At last, the perfection measures were put forward.