In this study, there are examined to the grounding of lightning protection system and electrical continuity tests in the field. The standard for lightning protection system is different design or construction according to the characteristics of the structure. Ground is measured and compared at least four locations. According to the measured results in the field, the sampled values of the ground resistance are measured $5{Omega}$ or less and the difference between each value is suitable as $0.2{Omega}$ or less. The values of the electrical continuity test between ground and metal bodies are measured 3 groups such as isolated portion, the mechanical contacted portion, and the electrical continuity portion measuring $0.2{Omega}$ or less. It is measured to be less than $0.2{Omega}$ at all in metal bodies of underground. A metal body installed inside the structure is not isolated, but the resistance values are higher than $0.2{Omega}$. Therefore, It must be carried out the structure having lightning protection system confirm the LPL(lightning protection level) and design the strategy.