Configuration and working principle of a DC non-transferred plasma torch have been introduced.Con- nections between the electric-thermal characteristics and operational parameter such as flowing gas flow rate and arc power have been investigated.Influence of high-speed lateral gas on jet figure has been analyzed synchronously.The results indicate that anode geometry affect plasma jet characteristics strongly.Arc voltage drops when the compressed angle increase;the stability of jet with less compressed angle is better;rigidity of jet with less anodic diameter is stronger.Plasma torches with different anode have respective applied fields.