Abstract: It is one of the most effective ways to use laboratory long air gap discharges for investigating the fundamental process involved in the lightning attachment.The research development on the lightning striking distance,the lightning simulation test and the positive upward connecting leader process by using laboratory long sparks were reviewed in this paper.According to the discharge observation results with the gap length up to 6m carried out in this paper,it is acceptable by using electric geometric model（EGM） to estimate the lightning shielding performance of small scale grounded objects,the existing lightning shielding simulation test does not take into account of the influence of upward connecting leaders,and the early streamer emission（ESE） device does not have the specified performance as it claimed.The lightning shielding performance investigation of large scale objects should focus on the inception and propagation of the positive upward leader,which aims to develop the simulation test methods of positive upward leader by using long sparks and to modify the physical simulation models.