Bacillus Calmette-Guerin (BCG) is one of the most effective treatments for bladder cancer. Little attention has been paid to the possible role of neutrophils in BCG immunotherapy. In this study, we examined neutrophil extracellular traps (NETs) formation induced by BCG stimulation, and found that BCG-induced NETs exerted cytotoxicity, induced apoptosis and cell-cycle arrest, and inhibited migration in bladder tumor cells.