Abstract: An experimental investigation of pulsed Nd³⁺: YAG active-passive mode-locked laser system is reported. The pulse width measured by the noncollinear SHG technique was about 40 psec. The amplitude stability and mode locking probability of the ultrashort pulses produced by this system were compared with that by the purely passive mode-locked system under the same operating conditions. Effect of dye concentration on the width of the mode-locked pulses was also studied.