Neutrophils are the first line of defense against invading pathogens. Neutrophils kill pathogens through chemotaxis and phagocytosis. It has been confirmed that neutrophils kill pathogenic microorganisms by engulfing pathogens and secreting antimicrobial protein particles. In 2004, Brinkmann found a new anti-infection mechanism of neutrophils, that is the release of neutrophil extracellular traps (NETs) after activation. NETs are a kind of structure similar to fiber network, which are composed of double-stranded DNA and antibacterial proteins laying on chromatin structure. The role of NETs in the process of anti-infection is capturing and killing pathogenic microorganisms. In recent years, increased evidence has shown that NETs play an important role in inflammatory diseases, and the pathological process in acute and chronic inflammatory diseases would be affected by NET generation and degradation. This article mainly summarizes the latest research progress on NETs in the characteristics, generation mechanism, antibacterial activity, and the effect in inflammatory diseases; provides new ideas and directions for the treatment and drug development for inflammatory diseases.