The river-bed sediments from the major river basins were analysed for the chemical and physical properties to evaluate environmental safety for the agricultural uses. The samples were taken from 16 sites of Han river, 36 of Geumgang river, 27 of Yeongsan river, and 140 of Nakdong river. The total of 219 samples from the 28 counties were taken from the surface of the sediments at the depth of 50 cm. The particle density of the sediments was greater than 2.63 Mg m^-3 and the whole range of the density was 2.60∼2.69 Mg m^-3, the average particle size was 0.7 mm whereas the size range was 0.075∼0.85 mm. The analyses of the particle sizes by basins showed that Han and Geumgang river had particle sizes of 0.075∼0.85 mm, while Geumgang and Yeongsan river had particle sizes of 0.25∼0.85 mm. Geumgang and Yeongsan river tended to have greater particle sizes. The average values of the chemical properties were 6.3 for pH, 0.16 dS m^-1 for EC, 8 g kg^-1 for organic matter, 101 mg kg^-1 for available phosphate, 0.39, 3.47, and 0.93 cmol_c kg^-1 for exchangeable potassium, calcium, and magnesium respectively. The greatest property at each basin was pH for Han river, Ec, available phosphate and exchangeable sodium for Geumgang river, organic matter, exchangeable calcium and magnesium for Yeongsan river, and exchangeable potassium for Nakdong river.