Abstract: In this paper, the neutralization theory which is regarded as the theoretical fundament of lightning e-liminator and some concrete instances which the lightning stroke can not be eliminated by lightning eliminator are introduced. The authors point out that the key that lightning eliminator can eliminate lightning stroke is whether lightning eliminator could produce enough corona current to neutralize the charge in a thunder cloud under the thunder cloud electric field. The following conclusions are obtained by analyzing the test results of corona current of conductor multi-rods lightning eliminator with respect to lightning rod. There being a charge of 20~100 C coulombs in a general thunder cloud, it would take lightning eliminator about 80 hours to neutralize a charge of 20 coulombs. Lightning eliminator cannot neutralize this charge in only 2. 7 minutes because a thunder cloud spends 2. 7 minutes in drifting its way through a building. Considering a charge of 20 coulombs in a thunder cloud and a flash rate of per two minute, 670 mA of corona current would be required to neutralize this charge in 30 seconds in order to prevent a lightning stroke. There is only 70 μA of conductor multi-rods lightning eliminator, therefore, lightning eliminator cannot eliminate lightning stroke. It is suggested that the lightning eliminator cannot be applied in engineering up to now.