The accumulation of hydrophobic bile acids in the liver is considered to play a pivotal role in the induction of apoptosis of hepatocytes during cholestasis. Thus, factors that affect apoptosis may be used to modulate liver fibrosis. Yin-Chen-Hao-Tang (YCHT) decoctions have been recognised as a hepatoprotective agent for jaundice and various types of liver diseases. We used an experimental rat model of bile-duct ligation (BDL) to test whether YCHT plays a regulatory role in the pathogenesis of hepatic apoptosis. BDL-plus-YCHT groups received 250 or 500 mg kg (-1) YCHT by gavage once daily for 27 days. YCHT significantly ameliorated the portal hypertensive state and serum TNF-alpha compared with the vehicle-treated control group. In BDL-plus-YCHT-treated rats, hepatic glutathione contents were significantly higher than than in BDL-only rats. BDL caused a prominent liver apoptosis that was supported by an increase in Bax and cytochrome c protein and increased expression of Bax and Bcl-2 messenger RNA. The normalising effect of YCHT on expression of Bax and Bcl-2 mRNA was dependent on the dose of YCHT, 500 mg kg (-1) having the greater effect on both Bax and Bcl-2 of mRNA levels. Additionally, YCHT treatment down-regulated both hepatic caspase-3 and -8 activities of BDL rats. This study demonstrates the anti-apoptotic properties of YCHT and suggests a potential application of YCHT in the clinical management of hepatic disease resulting from biliary obstruction.