Neutrophil extracellular traps (NETs) are networks of extracellular structures, primarily composed of decondensed nuclear chromatin and associated proteins, which are released by activated neutrophils. NETs protect against infection. Recently, they have also been found to exist in pathological environments of various diseases and are closely related to the occurrence and development of diseases. In this review, we briefly summarize the research progress in the roles and mechanisms of NETs in pathogenesis of several autoimmune diseases such as psoriasis, systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), anti-neutrophil cytoplasmic antibodies (ANCA)-associated vasculitis (AAV), and type 1 diabetes (T1D).