Covalent organic frameworks (COFs) are a class of organic porous polymers with high crystallinity, and their structures can be precisely tailored via topology design. Owing to the characteristics of permanent pores, periodic structures and rich building blocks, COFs have triggered tremendous attention in the past fifteen years and are extensively investigated in various fields. Crystallinity and stability are two crucial features for practical applications. In general, these two features are contradictory for COFs formed via dynamic covalent chemistry (DCC). High thermodynamic reversibility is usually required to attain exceptional crystallinity of COFs, often resulting in limited stability. The first two reported COFs are based on the boroxine and boronate ester linkages, which are unstable in water and even in humid conditions. Therefore, many researchers doubt the stability of COFs for real applications. Actually, in these years, various novel linkages have been developed for the construction of COFs, and numerous newly synthesized COFs are robust towards strong acid/base and even some of them can resist the attack of strong oxidizing and reducing agents. In this review, we focus on the linkage chemistry of the COFs in terms of crystallinity and stability, further extending it to the investigation in the mechanisms of the crystal growth and the overall regulation of the contradiction between stability and crystallinity. The strategies for improving the crystallinity, including selecting building units, introducing non-covalent interactions and slowing nucleation and growth rate, are described in the third section, while the methodologies for increasing the stability from the viewpoints of chemical modification and non-covalent interactions are summarized in the fourth section. Finally, the challenges and perspectives are presented.

共价有机骨架（COF）是一类具有高结晶度的有机多孔聚合物，可以通过拓扑设计精确地定制其结构。由于永久性孔隙，周期性结构和丰富的构造块的特性，COF在过去的15年中引起了极大的关注，并在各个领域进行了广泛的研究。结晶度和稳定性是实际应用中的两个关键特征。通常，这两个特征与通过动态共价化学（DCC）。通常需要高的热力学可逆性才能获得出色的COF结晶度，从而经常导致稳定性有限。报道的前两个COF基于硼环素和硼酸酯键，它们在水中甚至在潮湿条件下都不稳定。因此，许多研究人员怀疑COF在实际应用中的稳定性。实际上，近年来，已经开发出各种新颖的键用于COF的构建，并且许多新合成的COF对强酸/碱具有鲁棒性，甚至它们中的一些可以抵抗强氧化剂和还原剂的攻击。在这篇综述中，我们专注于COF的键合化学，包括结晶度和稳定性，进一步将其扩展到晶体生长机理的研究以及稳定性和结晶度之间矛盾的整体调节。第三部分介绍了改善结晶度的策略，包括选择结构单元，引入非共价相互作用以及减缓成核和生长速率，而从化学修饰和非共价相互作用的角度来看，提高稳定性的方法则包括总结在第四部分。最后，提出了挑战和观点。第四部分总结了从化学修饰和非共价相互作用的角度提高稳定性的方法。最后，提出了挑战和观点。第四部分总结了从化学修饰和非共价相互作用的角度提高稳定性的方法。最后，提出了挑战和观点。