Abstract: The detailed analysis of charging process in the pulsed intense-electron-beamaccelerator is presented. And the expression of voltage-transition coefficient isdeduced as well. This expression is expressed in terms of characteristic rootsof the characteristic equation which is transfered from the differential equation ofcharging circuit of Blumlein line by means of Laplace transform. Proximate expressions and reasonable explanation to the physical connotationof characteristic roots in our solution are given. Formulas and methods with which one can easily calculate some of dynamicparameters of accelerator directly from voltage waveforms measured duringadjusting are acquired, therefore, they have great significance not only foradjustment but also for design and improvement of this kind of machine.