Cognitive decline affects the physical function of the elderly in communities and is closely related to the occurrence, development, and adverse outcomes. By reviewing the concept, screening tools, current status, and significance of cognitive decline in the elderly in communities at home and abroad, in this article, we compared and analyzed the differences resulting from screening methods and tools for cognitive decline in order to improve the screening rate of cognitive decline in the elderly in communities in China and provide a more scientific basis for the development of accurate intervention measures.