In this study we examined the effect of propofol on somatic and visceral pain in mice. A thermal method (tail immersion) and a chemical method (acetic-acid-induced writhing) were used to determine the antinociceptive effect of propofol. First we determined the dose-response relationships of propofol with a preliminary study. Then propofol was administered according to the results of the preliminary experiment. We used the subhypnotic and nonsedative doses of propofol in the experiments. This dose was lower than 10 mg/kg for mice according to our findings, and ED50 sedation for propofol was 33 mg/kg. Propofol retarded tail withdrawal latencies and decreased writhing numbers of mice in a dose-dependent manner in dosages of 10 and 5 mg/kg (P < 0.001 and P < 0.01, respectively). It was not different from the control group in the dosage of 2.5 mg/kg (P > 0.05). These results suggest that propofol has an antinociceptive effect on visceral as well as on somatic pain when given in subhypnotic doses.