In short arc milling of nickel based superalloy (GH4169), the simulation and calculation of short arc milling thermal field using the finite element analysis (FEA) software, is validated by experiments.The pulse voltage and frequency on the duty ratio of short arc machining heat affected layer influence law was analyzed.The results show that under certain frequency, when the duty ratio is constant, the size of the thermal effect on the change of the voltage of the workpiece layer has little effect; while keeping the voltage constant, with the increase of the duty ratio, the heat affected the workpiece thickness also increases accordingly.