A large portion of the Yellow Sea is floored by fine-grained clastics derived largely from the Hwangho and Yangtze Rivers. In the southeastern Yellow Sea, however, coarse-grained sediments prevail, derived probably from the short and steep Korean rivers. Farther east the coarse-grained sediments contain substantial amounts of fine fractions. Near the Keum Estuary detrital clays such as kaolinite and chlorite are abundant in the free fractions and this trend extends for about 120 km both toward the northwest and the southwest. Illite appears to be dominant in the rest of the Yellow Sea. The data suggest that the bulk of fine-grained sediments in the southeastern Yellow Sea originates from the Keum River. The sediments are subsequently transported by prevailing nearshore currents both northwestward during summer and southwestward in winter. The tidal currents may also play a role. The close correspondance between the oceanographic data and the mineralogic evidence suggests that the dispersal of fine-grained sediments in the southeastern Yellow Sea occurs largely under the steady-state conditions.