Abstract: As a result of self-phase modulation(SPM),the frequency chirp is imposed on optical pulses when the optical pulses are amplified in gain-saturated traveling-wave semiconductor laser amplifiers,The proper impressed chirp results in not only canceling the primary chirp of input pulses,but also possibly compressing pulses with a simple group velocity delay line. In this paper,the shape of the amplified output pulses and impressed frequency chirp are calculated for different input pulses,and the effect on chirp compensation of using optical amplifier is analyzed.