The systemic and hepatic circulation of 20 adult mongrel dogs was examined during and after inhalation of 2% (OE2%) and 3% (OE3%) enflurane in oxygen. A high correlation (r=0.83) was noted between CI and PVBF. A correlation between CI and HABF was recognized at the higher concentration of the anesthetic : r=0.03 in the OE2% group, and r=0.60 in the OE3% group. The systemic vascular resistance (SVR) and mesenteric vascular resistance (MVR) changed similarly in the OE2% and OE3% groups, and the disturbance of the systemic blood flow distribution was considered slight. SVR and MVR increased similarly to levels significantly above the control levels after termination of enflurane inhalation in both groups. The hepatic arterial vascular resistance (HAVR) during inhalation was lower than either SVR or MVR, and was sighificantly lower than the control level in both groups. However, after the inhalation was terminated, there no longer was a significant difference between the experimental and control HAVR. Since SVR and MVR changed similarly at both concentrations of enflurane, disturbance of the systemic blood flow distribution was thought to be small. It was clear that the decrease in HABF was less than the decrease in PVBF.