The effects of soil-water content (0), electrical conductivity of soil water (EC), and clay content of a soil on the bulk-soil electrical conductivity (ECb) were investigated by a series of contecilled laboratory experiments. The bulk-soil electrical conductivity increases nonlinearly with increasing soil-water content and soil-water electrical conductivity. ECb, although a unique function of soil-water content in sand, is a combined function of soil-water content and electrical conductivity of soil mineral (ECs). in sandy loam and silt loam soil. The bulk-soil electrical conductivity is greater in silt loam soil than in sandy soil and sandy loam soil due to the higher content of clay in the silt loam soil than in the Other tWO soils. The bulk-soil electrical conductivity increases with increasing clay content of the soils for the same soil-water contents and constant soil-water electrical conductivity in all three soils.