Sapphire is an important wide bandgap semiconductor material for developing UV/blue optoelectronic devices, however because of its high hardness and chemical stability; it is mechanically and chemically difficult machine. In this paper, the scribing of sapphire by UV laser pulses is investigated under various conditions of pulse energies, scanning speed and repetition rate. The quality and morphology of the laser ablation of sapphire surface are evaluated by scanning electron microscopy. The mechanism of UV laser ablation of sapphire is discussed. The formation of grooves with high aspect ratio and good surface quality is achieved by selecting appropriate laser parameters. Scribing by pulsed UV laser therefore provide a new approach in the development of sapphire-based devices.