Abstract:As an extremely important organelle in eukaryotic cells, endoplasmic reticulum (ER) plays a key role in the synthesis and processing of biomacromolecules, material transport, ion homeostasis maintenance, signal transduction, exchange of materials and signals between organelles. Many important human diseases, such as cancers, autoimmune diseases, pathogenic infections, neurodegenerative diseases and diabetes, are closely related to ER dysfunction. With the development of nanotechnology, the exploration and application of ER-targeted nanodrugs gradually become a research hotspot in the field of nanomedicine, bioengineering, material chemistry and other fields. In this paper, the relationship between ER dysfunction and disease occurrence, the principle of designing ER-targeted nanodrugs and their biomedical application are reviewed. ER-targeted nanodrugs are designed based on nanodrug carriers or self-assembly of bioactive molecules. These nanodrugs could target the ER in an active or passive manner and function by disrupting or maintaining the ER functions. The ER-targeting nanodrugs have a wide application prospect in cancer therapy, immune regulation, nervous system repairment, and so on.