Biological Soil Crusts （BSCs） can be used as a model system to study complex ecological issues. As a continuous water source， hygroscopic condensate is most important factor to the survival of BSCs in dry conditions， which influences the physiological activities of BSCs and soil carbon exchange and other biogeochemical processes. Therefore， the relationship between hygroscopic condensate and BSCs is particularly important in desert ecosystem. Considering the formation process of hygroscopic condensate is affected by underlying surface characteristics and many thermal and meteorological environmental factors， the cross-integrated research based on soil science， biology， meteorology， physics， surface science and other disciplines is proper for this study topic. This paper reviews the latest research trends on hygroscopic condensate and BSCs relationship， analyzes the advantages and disadvantages for different measurement methods and their development tendency， summarizes the effect mechanism of hygroscopic condensation to BSCs and the influence of BSCs growth on the formation of hygroscopic condensation， discusses the evolution and deficiency of current research on the relationship between hygroscopic condensation formation and BSCs based on above two aspects， states the change of non-rainfall water input and its ecological effect to BSCs growth and desert ecosystem function under the condition of future global changes. Furthermore， we put forward the existing problems in current research and the research priorities in future. The solution of these problems will improve our scientific understanding about the stability and sustainability of desert ecosystems.