In hepatocellular carcinoma, anatomical resection is important because of portal spread. In right anterior sectionectomy (RAS) and right posterior sectionectomy (RPS), the right hepatic vein (RHV) may not correspond with the intersectional plane if an inferior RHV (IRHV) is present. The aim of this study was to evaluate the influence of the IRHV on the exposure of the RHV retrospectively. One hundred ninety-one patients underwent RAS or RPS by the Glissonean pedicle transection method. The calibres of the RHV and IRHV were measured and assessed the extent of exposure of RHV. One hundred seventeen patients underwent RAS and 74 underwent RPS. The calibre of the RHV averaged 8.0 mm and that of the IRHV, 6.2 mm. Exposure of the RHV was divided into three groups: no exposure 31 (16.2%) (with IRHV, 20 patients; without IRHV, 11 patients), upper half exposure 49 (25.7%; with IRHV, 24; without IRHV, 25) and full exposure 111 (58.1%) (with IRHV, 16; without IRHV, 95). The effect of the IRHV on exposure of the RHV was substantial (P < 0.001). The IRHV can affect the course of the RHV and its exposure. Therefore, in RAS and RPS, it is important to evaluate the existence of the IRHV.