Compatibility is the key factor to determine whether a prescription is effective, is the core of the theory of traditional Chinese medicine, and is also the key issue to study prescriptions and improve clinical efficacy. Scholars mostly study the compatibility law from the following three aspects: traditional theoretical research; research with different entry points, such as whole prescription, split prescription and drug equivalence; multi discipline research, such as statistics, evidence-based medicine, chemistry and pharmacology, network pharmacology, et al. At present, there are many researches on compatibility laws, but most of them have some limitations. This paper reviews the research on the above aspects in recent years, hoping to provide some reference for the guiding principles, research objects, research entry points, reasoning tools, research tools, verification tools and possible future development directions of the research on compatibility laws.