Abstract: During operation of XX adjustment well in a oil and gas field of East China Sea,after drilling to the depth of design,it is decided to continue drilling to explore oil and gas bearing conditions of deeper formation.During drilling process,overflow occurred when drilling to 5 108 m.When killing the well,drill pipe piercement occurred at 731 m,resulting in short circulation.When displacement killing method was applied,circulation loss and choke line piercement occurred,which lead to further complications with insufficient pressure level of equipment.After a series of unconventional well kill techniques,killing well is successful.It is a successful case of well killing.