Abstract: The work studies the evolution characteristics of the plasma channel in high power pulsed xenonflashlamps. Various influence factors are analyzed, including the charging voltage, the main pulse width, and the time interval between the pre-ionization pulse and the main pulse. Distinct branching phenomena are observed near the grounding terminal of the flashlamps. It is found that the electric field distribution in the flashlamps working environment has the most significant influence on the evolution process of the plasma channel. Moreover, the electric field distribution determines the shape of the plasma channel, while other factors influence its brightness and uniformity.