Through a systematic review of research progress on mechanical test equipment for soil-structure interfaces, key influencing factors, numerical simulation methods, and constitutive models, the engineering applicability and technical limitations of current test equipment were analyzed, the response laws of interface mechanical properties under the influence of multiple factors were clarified, the key technologies and theoretical limitations in existing numerical simulations were summarized, and the applicable ranges and boundary conditions of commonly used constitutive models were classified. In light of the actual engineering needs and technological development trends, future research should focus on developing intelligent testing systems with integrated stress-seepage-temperature multi-field coupling functions, revealing the time-varying laws of interface mechanical properties under long-term complex environments and multi-field coupling, improving the numerical simulation method system based on the thin-layer element theory, and constructing intelligent constitutive models integrating machine learning algorithms and multi-source engineering data to enhance the accuracy and adaptability of interface mechanical behavior prediction under complex conditions.