Objective To investigate the effects of cimetidine on the red cell immune function and interleukin-2(IL-2) in rats with obstructive jaundice. Methods Sixty SD rats were divided into bile duct ligation(BDL) group, cimetidine therapy (BDLC) group and sham operation(SO) group respectively. The red cell immue function and serum IL-2 level were determined with the red cell yeast-rosttes test and radioimmunoassay respectively. Results The red blood cell C3b receptor rosette rate(RBC-C3bRR), the red blood cell immune complex rosette rate(RICR), the red blood cell C3b receptor rosette-forming excited rate(RFER) and serum IL-2 level were significantly lower in BDL group as compared with SO group, the red blood cell C3b receptor rosette-forming inhibitory rate(RFIR) in BDL group was higher than that of SO group. After 7 days’ cimetidine therapy RBCC3bRR, RICR, RFER and IL-2 became higher than those of BDL group, but RFIR was lower than that of BDL group. Conclusion Supplemental cimetidine can significantly enhance the impaired red cell immune function and IL-2 production in rats with obstructive jaundice.