Background and Aims: Complications and hepatic insufficiency are likely to occur in patients with liver tumor and concomitant liver cirrhosis after hepatectomy due to the always presence of poor liver functional reserve. So, accurate preoperative clinical assessment and precise intraoperative resection scope are of great importance for the outcomes of patients with liver tumor and concomitant liver cirrhosis undergoing hepatectomy. This study was conducted to investigate the efficacy of using three-dimensional visualization technology (3DVT) combined with indocyanine green (ICG) clearance test in operation for patients with liver tumor and cirrhosis. 
Methods: The clinical data of 57 patients with liver tumor and cirrhosis undergoing hepatectomy with 3DVT plus ICG clearance assessment from May 2019 to March 2020 (observation group), as well as 62 patients with the same conditions undergoing hepatectomy with 3DVT plus traditional Child-Pugh assessment from January 2018 to April 2019 (control group) were retrospectively analyzed. The main clinical variables and the incidence rates of postoperative liver dysfunction and other complications were compared between the two groups of patients. 
Results: There were no significant differences in the basic data and each inflammatory factor and liver function parameter between the two groups before operation (all P>0.05). The operative time showed no significant difference between the two groups (P>0.05), but the intraoperative blood loss and length of hospital stay were reduced in observation group compared with control group (both P<0.05). In either group, all inflammatory factors and liver function parameters were significantly improved compared to preoperative values, but the improving degrees of them in observation group were significantly superior to those in control group (all P<0.05). The overall incidence rates of postoperative liver dysfunction and complications in observation group were significantly lower than those in control group (both P<0.05). 
Conclusion: Using 3DVT plus ICG clearance test in operation for patients with liver tumor and concomitant liver cirrhosis is helpful for accurate preoperative judgment of the space structure relations between liver tumor and surrounding tissues, determination of the liver resection volume and residual liver volume, and estimation of the liver functional reserve, and also can reduce the intraoperative blood loss and postoperative traumatic stress reactions of the patients, shorten hospitalization time, and decrease the incidence rates of postoperative complications and hepatic insufficiency. So, it has good application value and is recommended to be used.