Abstract: In this paper, the influence of different pulse fiber laser processing parameters (pulse power, pulse frequency, pulse width and cutting speed) on the geometry of 46MnVS5 cracking groove of a new expanded connecting rod material is analyzed and summarized. The results show that with the increase of pulse power, pulse frequency and pulse width, the depth and width of cracking tank increase in varying degrees. Among them, the pulse power has a great influence on the opening angle, but the change of pulse frequency and pulse width on the opening angle is not obvious; The groove depth and width decrease with the increase of cutting speed, and the opening angle changes in a certain size range. When the processed groove depth is between 450~700 μm and the groove width is between 150~200 μm, the opening angle changes in the range of 15°~20°, which can meet the processing requirements.