In this study, we evaluated the diagnosis, epidemiology, risk factors, and treatment of chylous ascites developing after liver transplantation (LT). Between 2002 and 2011, LT was performed 693 times in 631 patients at our clinic. One-hundred fifteen of these patients were excluded for reasons such as retransplantation, early postoperative mortality, and insufficient data. Chylous ascites developed after LT (mean +/- SD = 8.0 +/- 3.2 days, range = 5-17 days) in 24 of the 516 patients included in this study. Using univariate and multivariate analyses, we examined whether the following were risk factors for developing chylous ascites: age, sex, body mass index, graft-to-recipient weight ratio, Model for End-Stage Liver Disease score, vena cava cross-clamping time, total operation time, Child-Pugh classification, sodium level, portal vein thrombosis or ascites before transplantation, donor type, albumin level, and perihepatic dissection technique [LigaSure vessel sealing system (LVSS) versus conventional suture ligation]. According to a univariate analysis, a low albumin level (P = 0.04), the presence of ascites before transplantation (P = 0.03), and the use of LVSS for perihepatic dissection (P < 0.01) were risk factors for developing chylous ascites. According to a multivariate Cox proportional hazards model, the presence of pretransplant ascites [P = 0.04, hazard ratio (HR) = 2.8, 95% confidence interval (CI) = 1.1-13.5] and the use of LVSS for perihepatic dissection (P = 0.01, HR = 5.4, 95% CI = 1.5-34.4) were independent risk factors. In conclusion, the presence of preoperative ascites and the use of LVSS for perihepatic dissection are independent risk factors for the formation of chylous ascites. To our knowledge, this study is the most extensive examination of the development of chylous ascites. Nevertheless, our results should be supported by new prospective trials. Liver Transpl, 2012. (C) 2012 AASLD.