A new laser pulse-shaping system using an electro-optic modulator driven by an aperture-coupled-striplines (ACSL) electrical-waveform generator has been discussed in this paper. The ACSL electrical-waveform generator consists of two striplines coupled through an aperture in their common ground plane. Replacing the aperture layer, the electrical-waveform can produce arbitrary electrical pulse with 150 ps structure. Giving the arbitrary electrical pulse to the electro-optic modulator, arbitrary optic pulse can be gotten. By the new technique, the laser pulse-shaping system is capable of producing arbitrarily shaped laser pulses with about 150 ps structure, 1～3 ns pulse envelope, high contrast waveform and slippery transition waveform.