Neutrophil extracellular trapping nets (NETs) are reticular fibrous structures composed of DNA, histone, granule protein and cytoplasmic protein released by neutrophils under the stimulation of bacteria, fungi, viruses, and parasites. According to different stimuli, the formation of NETs mainly falls into two categories: non-nicotinamide adenine dinucleotide phosphate oxidase-dependent pathway and nicotinamide adenine dinucleotide phosphate oxidase-dependent pathway. NETs have both anti-inflammatory and pro-inflammatory effects. On the one hand, they can capture, fix and kill invading pathogens, playing an antimicrobial role, and help inflammation subside. This is a special way for neutrophils to play host defense. On the other hand, when it produces too much or clearance is insufficient, it can directly cause tissue damage, but also recruit other pro-inflammatory cells or proteins to promote the release of inflammatory factors, further to expand the inflammatory response and participate in the pathological damage of a variety of diseases. Therefore, the authors by summarizing the relationship between NETs and lung diseases, liver diseases, intestinal diseases, tumors, and other diseases reveal the roles of abnormal formation and clearance of NETs in tissue and organ injury, to explain the occurrence mechanism of some clinical diseases, and also provide important direction guidance and theoretical basis for exploring the relevant mechanism of drug intervention in NETs and targeted therapy.