Abstract: Simulations of kinetics in the laser cavity with electron-beam-pumping, also processes of laser production, amplification and transport in different injected fluxes and different inject time are presented. The one-dimensional approximation is used for the practical unstable resonator, and the transport equation is numerically integrated with the predictor -corrector method. The result shows that the quality of laser output is obviously improved with injected seed signal and the spontaneous emission is obviously. This simulation also demonstrates the spectral characteristic, the energy, and various efficiencies of the laser output. We also find that the injected time of the best locking efficiency is that moment when the small signal gain reaches the maximum value. The theoretical calculation of the laser output is in agreement with experiment of the parallel cavity and unstable resonator in different conditions.