The influence of dexamethasone (DEX) on proliferative activity and bile salt concentration in primary culture of rat hepatocytes were investigated. Isolated liver cells were cultured with 10⁻³ M of cholesterol, and with 10⁻³ M of cholesterol and addition of 10⁻⁶, 10⁻⁸, or 10⁻¹⁰ M of DEX. After 24, 48, and 72 h, the cell proliferation, bile salt concentration ,and profile were examined. The proliferative activity of control hepatocytes ranged between 0.841 ±0.05 and 0.937 ±0.007. In opposite to 10⁻⁸ M DEX, the addition of 10⁻⁶ and 10⁻¹⁰ M of DEX resulted in a decrease in proliferative activity of cells after 48 h of incubation (0.5 i 9±0.12 and 0.533+0.13, respectively). The presence of DEX resulted in elevation ofbile salt level in samples obtained after 72 h (3.97+1.2 µM/L; 3.42±2.0 µM/L, and 3.52+0.3 µM/L in the presence of 10⁻⁶ M, 10⁻⁸ M, and 10⁻¹⁰ M of DEX, respectively). Proliferative response of rat hepatocytes to DEX depended on dose and incubation time. DEX in the highest concentration intensified the bile salts synthesis much earlier than under other experimental conditions. Among the analysed bile salts, cholic and deoxycholic acids predominated. They were conjugated mostly with taurine and to a lesser extent with glicine.