Objective To compare the curative effects between ursodeoxycholic acid (UDCA) and S-adenosyl methionine (SAM) in the treatment of biliary cirrhosis.Methods A prospective study was made on 80 patients with primary biliary cirrhosis, who were divided randomly into an observation group and a control group, and the two groups were administered with Diammonium Glycyrrhizinate, reduced glutathione, Potassium Aspartate magnesium, and calcium; on the basis of this, the observation group was additionally administered with UDCA capsule and the control group with SAM-B injection. Both groups were treated and observed for three consecutive months. divided randomly into an observation group and a control group, and the two groups were administered with Diammonium Glycyrrhizinate, reduced glutathione, Potassium Aspartate magnesium, and calcium; on the basis of this, the observation group was additionally administered with UDCA capsule and the control group with SAM-B injection. Both groups were treated and observed for three consecutive months.Results After the treatment, the total effective rate in the observation group (97.5%) was significantly higher than that in the control group (85%) (P < 0.05); the serum ALT and AST values in the observation group were (32.87±12.10)U/L and (33.20±14.20)U/L, respectively, significantly lower than those in the control group (51.39±13.09)U/L and (51.49±14.22)U/L(P < 0.05). The CD4+ values in both groups were significantly lower than those before the treatment; the CD4+ value in the observation group were significantly lower than those in the control group (P < 0.05), whereas the CD8+ values in both groups before and after the treatment were not significantly changed (P > 0.05).Conclusion As an adjuvant medicine in the treatment of primary biliary cirrhosis, UDCAcan reduce the damage to the liver, improve the efficiency of treatment, and has better curative effect than SAM; its mechanism is probably related to the improvement of the cellular immune function of patients.