The semi-empirical model of arc impulse discharge development in impulse xenon lamps for optical pumping of solid-state lasers’ active media was considered. Equations of the power balance of supplied electrical power and processes of ionization, plasma heating, heat dissipation and optical radiation generation laid the model’s basis. The analytical description of the processes being considered results in an ordinary differential equation which allows a non-resource-intensive numerical solution. The built model enables to evaluate basic electrical and optical parameters of non-local arc discharge plasma at its development stage. Comparison with the results of measurements of electrical and optical plasma parameters which are the most convenient for experimental diagnostics in the modelled non-stationary mode testifies to adequacy of the developed model. Relative simplicity and convenience of the model predetermines its possible usage when solving applied engineering tasks of optimization of operating parameters of impulse pumping lamps and for obtaining initial (zero) approximations for comprehensive modelling of a non-local non-stationary gas discharge plasma in science-intensive calculations taking into account a great combination of elementary collision and radiation processes in a non-equilibrium system.