Lightning flash counter has been observed to know lightning density. It is most important to make the frequency distribution map of the lightning discharges in Japan. So that, the counter are required to investigate it's reliable in detail. Authors discussed the relation between lightning flash counter and field intensity, In the result, We could find out to have a character of the counter using ground flashes, could flashes and multiple-stroke lightning, Therefore, the observations to be cmpared the counter with field intensity are discussed in this report.
