Abstract: The distribution of high frequency pulse TIG welding arc anode average current density and the dynamic process of the said arc anode are determined in this paper. Their mathematical models are established, and the compression mechanism of high frequency pulse TIG welding is explored. The distribution of high frequency pulse TIG welding arc anode axial pressure has been studied by a self-made micro-pressure measuring device. And the related mathematical model is established as well. Experiments have shown that high frequency pulse TIG welding is a useful technique for welding precise super-thin plates. An adaptive pulse frequency of about 20kHz is recommended.