Abstract: According laser rate equations,the dynamic characteristics of pulsed Ti:sapphire laser has been comprehensively studied.The theoretical study and experimental results prove,if duration of pumping pulse is much less the life of up energy level,(1)the width and waveform of the output pulse is independent of the pumping pulse,(2)the only factor of determining the output pulsewidth is the ratio of pumping energy to threshold pumping energy,(3)the time delay of output pulse is dependent of the pumping pulsewidth and the ratio of pumping energy to threshold pumping energy.