The flight activity of moths was monitored by using infra-red video recorder and flight mill.Few activities were observed as the moths were just after emergence. Their night flight became vigorous after the moths came up to one day old, and there were two peak flight stages in 20:00～21:00 and 3:00～5:00 O'clock.The 1～3 days old moths mainly flew for feeding and mating, and mainly for oviposition after they were more than 3 days old.The flight ability of 3～6 days old moths was the strongest.The mean and the l...