Objective To gain accurate imaging i nformation of biliary tract after surgery. Methods The biliary tract of 170 cases after s urgery had been observed dynamically from different directions for longer time. The results of data on biliary tract change were stored in disc, or picture. Results Of 170 cases, 120 cases were cured with out any abnormal change on cholangiography, and then the T-tube was removed. Of another 50 cases, 30 cases revealed remnant stone on cholangiography, 9 cases s howed inflammatory stricture of biliary tract, 4 cases displayed common bile duc t tumor, and 7 cases had false filling-defect. Then, the results were further c onfirmed by sonography, CT, choledochoscopy, and operation. Conclusion The dynamic observation of biliary tract by T-tube cholangiography after surgery is usual way that is handy, pract ical, painless, and economic.