In this article we report on studies aimed at a theoretical description and an experiment design of generation of intense
THz pulsed laser. Through solving the time-independent rate equations, the absorption coefficient and the gain
coefficient of intense THz pulsed laser are obtained with the assumption of the pump rate and the induced transition rate
much larger than collision rate. The analysis further shows that at low pressure the absorption coefficient is proportional
to the second power of pressure and is in inverse proportion to pump intensity, and that the gain coefficient has the same
feature expect for being in inverse proportion to THz radiation intensity. Meanwhile the expressions of the saturation
pumping intensity and THz radiation intensity are given under the same assumption. On the other hand the expression of
energy absorbed from pump beam is derived from solving the time-dependent rate equations, and we demonstrate that
path length, gas pressure, and pulse width are the important factors impacting on the energy absorbed from pump beam.
When transmission of pump laser is determined, it is found that gain molecule mass, gas pressure and pulse width exist
an inner confine relation. Finally according to the theoretical analysis and some parameters assumed, we present an
experiment design of the intense THz pulsed laser.