The widespread utilization of engineering ceramics has been limited by fracture in the machining process. A technical basis for avoiding fracture requires a fundamental understanding of the fracture mechanisms in machining. The present paper is intended to discuss the fracture mechanisms during the vibration drilling of holes in engineering ceramics. In this paper, the stress distribution during the vibration drilling of holes in ceramics has been analysed. The results show that, in the terminal period of vibration drilling, the stress on the periphery of the hole exit is at its maximum. It is the main reason for fracture at the exit of holes in engineering ceramics. The condition for no fracture at the exit is given, and an eVective method is proposed to avoid such fracture.