BACKGROUND/AIMS To investigate the impact of liver resection on the perioperative hepatic function by evaluation of ICG-clearance. METHODOLOGY Twenty-five patients underwent major hepatic resection (Group A) and 36 underwent minor hepatic resection (Group B). Thirteen patients who received no liver surgery, acted as control group (Group C). ICG-clearance measured by a non-invasive technique was expressed in terms of plasma disappearance rate (PDR-ICG-%/min) and retention rate of ICG 15 min (ICG-R15-%) after administration ICG (0.5mg/kg) before anesthesia induction (T0), immediately after the surgery (T1) and 24h after (T2). RESULTS There was statistically significant differences between the three groups: ICG-PDR (p<0.004) and ICG-R15 (p<0.040). These differences were observed between groups A and C at T1, between A and B, or A and C, at T2 for ICG-PDR and between groups A and B at T2 for ICG-R15. There were no differences between groups for hemoglobin, platelets, PT, creatinine, albumin, total protein, bilirubin and ALP. CONCLUSIONS ICG clearance is a safe non-invasive dynamic tool to quantify the liver function in patients following hepatic surgery. It also can be used to evaluate the liver surgery impact on hepatic function which can help to diagnose early hepatic dysfunction and guide the therapeutic decision making process.