Based on the data collected from 164 hydrological stations, situated at the down-stream of rivers (3022 station year), up to 1979, this paper estimated the annual ave-rage of runoff and loads flowing into the seas from the rivers in littoral areas of China, they are approximately 1800 km3 and 2000 million tons respectively and accound for 4.6% and 11.5% of the total volume of the world, while the content of soluble substa-nce in the runoff is about the same as that of the world.Under annual average, the Donghai receives most of the discharge approximately 64.5% of the total, while Nanhai comes the next, as to the Pacific, it receives the least.The distribution of runoff that empties into the seas both in dry and wet years are comparable to that of annual average, the most apparent variation of dry and wet years is observed in Bohai, While Donghai and Pacific are not so apparent. As to the sedi-ments transportation, the Bohai also show the most apparent variation.During 1970-1979, both runoff and loads discharged into Bohai decreased and vice verse in the case of Nanhai.In addition to the impact of periodic variation of precipitation in drainage areas, the increase and decrease of runoff is also affected by human activities, as when the precipitation of drainage area varies little but due to human activities the runoff will decrease. Since the last decade, the amount of runoff discharged into Donghai decre-ased slightly, but the amount of loads increased accordingly, an iiicreasing of 5.4% has been observed.Year’s and seasonal variations of runoff and loads discharged into seas are con-trolled by the major rivers that emptied into the sea areas. The variation of runoff and loads of most rivers within the sea area are consistent with each other.