根据Ⅰ型裂缝和Ⅱ型裂缝在损伤与断裂耦合方面的联系，基于Ⅰ型裂缝的损伤方程推导出更适用于Ⅱ型裂缝的损伤演化方程，得到损伤区Ⅱ的计算方法。通过损伤梯度研究Ⅱ型裂缝从损伤至开裂阶段裂缝发展方向的变化规律，最终得到Ⅱ型裂缝的扩展角是79o。将该扩展角与经典判据得到的扩展角进行对比，结果表明该方法是可行的。“,”According to research on modeⅠand modeIIcrack damage coupled with fractures, a damage evolution equation that is more suitable for mode II cracks was established based on the damage equation of a mode Ⅰcrack. Then, the calculation method for the damage area was obtained. The variation of the direction in which the crack developed was studied using the damage gradient, over a period ranging from damage to cracking of the modeII crack. Finally, the propagation angle of the mode II crack was determined to be 79o. This propagation angle was compared with that obtained by the classic criterion. The results show that the method used in this study is feasible.