Arc　plasma　is　an　important　heat　source　for　manufacturing.　In　TIG　welding,　arc　properties　can　be　influenced　by　the　dynamic　thermal　behavior　in　the　cathode　region.　In　this　study,　to　experimentally　verify　the　focusing　feasibility　of　cathode　region　by　cooling　the　tungsten,　a　highly　cooled　tungsten　TIG　torch　was　proposed　and　designed.　Based　on　the　imaging　sensor　equipped　with　a　near-infrared　filter,　high　temperature　cathode　region　(HTCR)　images　in　the　cathode　tip　were　captured.　From　the　image　sequence,　height　and　width　of　the　HTCR　were　extracted　after　camera　calibration.　The　stagnation　ablation　experiments　were　carried　out　with　welding　currents　ranged　from　100　A　to　500　A.　In　the　highly　cooled　torch,　HTCR　size　parameters　were　smaller　comparing　to　those　obtained　with　the　less　cooled　torch,　the　resultant　anode　diameter　is　also　constricted　with　an　increasing　melting　depth.　The　focusing　effect　of　the　cathode　region　in　the　cooling　tungsten　was　experimentally　verified　and　was　analyzed　in　view　of　thermal　balance.　The　research　provides　a　new　method　to　modify　the　arc　properties　in　TIG　welding　process.