In the present paper, we evaluate the possible reduction in the rate of relapses in acute biliary pancreatitis through treatment with ursodeoxycholic acid (UCA), between the episode of pancreatitis and the moment of cholecystectomy. We studied 72 consecutive first episodes of acute biliary pancreatitis, in patients who had not yet undergone colecistectomy, followed up until surgery. The cases were divided into group A (n=30), treated with ursodeoxycholic acid 10 mg/kg/day, until surgery, and group B or control (n=42). We evaluated the differences between both groups, regarding patient characteristics, pancreatitis severity, characteristics of the lithiasis and delay until surgery. We analysed pancreatitis relapses in both groups, with and without UCA. In the UCA group we compared the duration of treatment between patients with and without pancreatitis relapse. The two groups did not show significant differences regarding any of the studied parameters. We registered 7/30 (23.3%) relapses in UCA group, versus 9/42 (21.4%) relapses in the control group (p = 0.85). In UCA group, treatment duration was similar between relapsed cases: 4.9+/-4.5 months and those without relapse: 4.4+/-1.9 months (p = 0.78). In our experience, the use of UCA until the moment of cholecystectomy does not reduce relapse incidence in patients following the first episode of acute biliary pancreatitis. UCA treatment duration did not seem to be related with the occurrence of pancreatitis relapse.