页岩的稳定性仍是钻井过程中面临的最重要问题之一。直到近期，稳定性问题大都归于页岩的膨胀；不过，最近的研究表明，它涉及几种原理，并且可以估计它们的相应的重要性。这篇论文评述了这几种原理，这些原理包括孔隙压力扩散、塑性、各向异性、毛细管效应、渗透和物理化学变化。孔隙压力扩散进井筒附近的岩石（由不排水转化为排泄状态），对于很低渗透率的岩石来说，似乎是很重要的。塑性可借助于模拟方法来讨论，与简单的模型比较，塑性模型能够较好地模拟井筒的实际情况。 The stability of shale is still one of the most important issues facing the drilling process. Until recently, most of the stability problems were attributed to shale expansion; however, recent studies show that it involves several principles and can estimate their relative importance. This paper reviews several principles, including pore pressure diffusion, plasticity, anisotropy, capillary effect, permeation and physico-chemical changes. Pore ​​pressure diffuses into rocks near the wellbore (from undrained to drained) and seems to be important for very low permeability rocks. Plasticity can be discussed by means of simulation. Compared with simple models, plastic model can well simulate the actual situation of wellbore.