Objective The aim of this study was to present a novel bile-duct obstructed area imaging (BOAI) and to investigate the feasibility and accuracy of this method in guiding hepatectomy for intrahepatic cholangiocarcinoma (ICC) with intrahepatic biliary obstruction. Methods From May 2017 to October 2019, eligible patients who underwent hepatectomy guided by BOAI were enrolled. Perioperative outcomes and operative data were analyzed. To assess the feasibility of BOAI and Glissonean pedicle approach, demarcations based on them were compared. To verify the accuracy of BOAI staining of the target territory, simple linear regression analysis, and intraclass correlation coefficient were used to examine the relationship between predicted resected liver volume (PRLV) and actual resected liver volume (ARLV). Results BOAI staining achieved valid demarcation in 15 (93.8%) of 16 patients, whereas the ischemic line achieved valid demarcation in only nine patients (57.3%;p = .017). ARLV and PRLV had a strong positive correlation (PRLV = 60.06 + 0.925 x ARLV;R = .945;p = .000). Meanwhile, ARLV (intraclass correlation coefficient = .971) achieved an excellent agreement with PRLV (p < .001). Conclusions The novel BOAI staining method can provide valid, feasible, and accurate demarcation line and may be an effective method in the surgical treatment of intrahepatic biliary obstruction.