The flood index series and drought index series are used to discuss the Periodic characters offlood/drought climate during 1470~1993 in the southeastern coast area in China.In drought series there exist significant Periodic components of 10,177,1 30,80,48 years in northern Partand of 10 ,80,1 12,41,12,30 years in southern pet of the area,while in find series thereexist significant Periods of 61,81,197,19 years in the north and of 37,23,124,14,80,10years in the south.From correlation analysis it is shown that long-term flood/drought variation isclosely associated with the 1 1-year and 22-year oscilation of solar activities,and with 19-year period of sun-moon-earth relative motion.The strong/weak century period of solar activity,tosome degree,also makes impact on long-term flood/drought variation.On this basis,the authorsgive an outlook on the trend of the long-term find/drought variation in the area.