Recent advances in patient selection and surgical technique have resulted in low mortality and morbidity rates after liver resections. The aim of this study was to evaluate the operative risks of liver trisectionectomies in comparison with major resections. The data prospectively collected of patients who underwent trisectionectomies (TR Group, n = 54) and major hepatectomies (MH Group, n = 175) without biliary reconstruction were compared. Besides, the early results of patients who underwent right trisectionectomies (RTR Group, n = 36) and left trisectionectomies (LTR Group, n = 18) were compared. There was no significant difference in patient characteristics of MH and TR groups excluded for a high portal vein embolization (PVE) in TR group. Mortality (1% in MH group and 3.7% in TR group, p = 0.206) and overall morbidity rates (39% in MH group and 48% in TR group, p = 0.225) were similar between two groups. A higher proportion of patients in TR group developed liver failure (p = 0.024) and required blood transfusion (30 vs. 11%, p < 0.001). The median hospital stay after trisectionectomies was higher in TR group than MH group (p = 0.053). There was no significant difference in patient characteristics of LTR and RTR groups excluded for lymphadenectomy which was higher in LTR group (p = 0.008) and PVE rate higher in RTR group (p = 0.01). The overall morbidity (44 vs. 55%) and mortality (2.7 vs. 5.5%) were comparable between two groups. A higher proportion of patients in RTR group required blood transfusion (39 vs. 11%, p = 0.032). At multivariate analysis, age was the only positive predictor for morbidity after trisectionectomies (p = 0.010). Trisectionectomies can be performed safely. Left trisectionectomies are as safe as right trisectionectomies. The accurate preoperative selection is necessary to reduce operative risks.