Abstract: Organelles have their special functions, they interact with each other and coordinate a series of important physiological functions at the same time. Organelle interaction occurs at membrane contact sites(MCSs), where the membranous organelle endoplasmic reticulum is the core, and specific tethered proteins at the membrane contact site bind to the organelle membrane and various protein complexes work together to perform specific functions, such as lipid transport, Ca²⁺ transfer, etc. This review studies on the structure and function of membrane contact sites and their key roles in organelle interactions, focusing on the connection between the endoplasmic reticulum and plasma membrane, mitochondria and Golgi, as well as the association between the key proteins at membrane contact sites and the occurrence and development of various diseases.