There were various reports that the occurrence rate of choledocholithiasis in Korea is higher than Occidental. Therefore, it is predicted that the frequency of retained or recurrent stone after biliary surgery for the choledocholithiasis may be high too, but it can be minimized if we apply more reliable operation method to various conditions of choledocholithiasis. A cornpara- tive retrospective clinical analysis was undertaken to assess the operative results in 100 con- secutive patients with choledocholithiasis who underwent choledochoduodenostomy(CDD group,' 51 cases) or transduodenal sphincteroplasty(TDS group,' 49 cases) during the period from May,1981 through October, 1992. Median duration of follow up was 45 rnonths(range 5 to 128 months) in CDD group and 38 months(range 7 to 98 months) in TDS group. The two groups were comparable with respect to age, operative urgency, associated disease and follow up duration except sex ratio. There was tendency of choice as first time operation in TDS group(82% vs 61%) rather than 2nd or 3rd time operation which were more frequently per- formed in CDD group(p<0.05). Main operative indication was CBD stone with combined IHD stones(61%) in CDD group and was impacted ampullary stone(49%) in TDS group. Mean di- ameter of CBD was greater in CDD group(2.3cm) cornpared to TDS group(1.6cm)(p<0.01). Median operative time and duration of hospital stay were shorter in CDD group compared to TDS group(139minutes vs 174minutes, p<0.001; 13days vs 17days, p<0.05 respectively). There was no difference in change of the postoperative liver function test between two groups. About 60 70% of patients with preoperatively elevated SGOT, SGPT, ALP and bilirubin value were returned to norrnal within 7 days following operations. Early postoperative evalua- tion revealed no differences between the CDD and TDS group with respect to retained stone (16% respectively), wound infection (4% vs 8%)(p=0.63) and operative mortality (2% vs 4 %)(p=0.97), but major and overall morbidity rate were higher in TDS group compared to CDD group (41% vs 20%, and 51% vs 25%, p<0.01, respectively). Late evaluation with long term follow up, showed no differences between the CDD and TDS group with respect to as- cending cholangitis(24% vs 12%, p=0.227), recurrent stone(12% vs 4%, p=0.295). These results lead to the conclusion that CDD is more safer, simpler, less time consuming procedure with short hospital stay and equal effectiveness compared to TDS, but TDS is primarily indicated in patients with impacted ampullary stone and srnall CBD diameter or biliary pancreatitis.(Korean J Gastroenterol 1994; 26: 683 689)