The tungsten carbide is a material with high hardness, wear resistance, good chemical stability, and dimensional stability. Because of these characteristics, it is mainly used as a tool for cutting and molding such as molds, and casts required for manufacturing high value-added equipment such as automobile parts and medical equipment. However, it is difficult to process with the traditional machining methods because of the high toughness and hardness. To overcome these problems, a study of tungsten carbide machining processing using the ultrafast-laser was recently conducted. In this paper, the ultrafast lasers with the pulse duration of 190 fs, 5 and 10 ps, respectively, were used. When the experiments were conducted with pulse widths of 5 and 10 ps, respectively, micro-cracks were observed from the heat generated by the overlap of the laser pulses. Conversely, the machining processing using a laser with the pulse width of 190 fs showed a major advantage with no crack by minimizing the thermal effects.