A prophylactic abdominal drainage catheter is routinely inserted by many surgeons in patients after hepatic resection. Between January 2002 and September 2004, 462 consecutive patients who had undergone hepatic resection using a clamp crushing method by the same surgical team were retrospectively divided into the drainage group (n = 357) and the nondrainage group (n = 105). There was no difference in hospital mortality between the two groups of patients (drainage group, 0.6% vs. nondrainage group, 0%; P = 1.0). However, there was a greater incidence of surgical complications in the drainage group (31.4% vs. 8.6%, P < 0.001), and greater incidence of wound complications and subphrenic complications in the drainage group compared to the nondrainage group (24.4% vs. 4.8%, P < 0.001). In addition, the mean (+/- SEM) postoperative hospital stay of the drainage group was 13 +/- 6.5 days, which was significantly longer than that of the nondrainage group (9.7 +/- 3.3 days, P = 0.001). On multivariate analysis, abdominal drainage and intraoperative bleeding were the independent risk factors that were significantly associated with the incidence of drainage-related complications. The results suggested that routine abdominal drainage is unnecessary after hepatic resection when the conventional clamp crushing method is used during parenchyma transection.