We developed segmental Lp-TAE, which is transcatheter hepatic sub-subsegmental, subsegmental, or segmental chemoembolization using Lipiodol introduced into the tumor-bearing hepatic sub-subsegment, subsegment, or segment as the target area. A total of 98 patients with nonresectable hepatocellular carcinoma (HCC) undergoing segmental Lp-TAE (Seg-Lp-TAE) were studied, and the relationship between the CT pattern observed after Seg-Lp-TAE (Seg-Lp-CT) and the therapeutic results obtained in those patients was evaluated. Seg-Lp-CT was classified into four types (type I, homogeneous; type II, defective; type III, inhomogeneous; and type IV, only slight accumulation, if any) according to the Lipiodol accumulation pattern observed after Seg-Lp-TAE. The cumulative nonrecurrence rates of type I were higher than those of types II-IV. The cumulative survival rates of type Ia, in which Lp accumulation is also seen around the main tumor, were the highest (93.8% at 1 year, 85.9% at 2 years, 85.9% at 3 years, and 57.3% at 4 years). The cumulative survival rates achieved with Seg-Lp-TAE were 89.2% at 1 year, 69.4% at 2 years, 58.9% at 3 years, 44.0% at 4 years, and 30.2% at 5 years, which were higher than those achieved with conventional Lp-TAE. Seg-Lp-TAE is very useful in the treatment of HCC limited to one sub-subsegment, subsegment, or segment, and it is important to choose sub-subsegmental, subsegmental, or segmental Lp-TAE on the basis of the size and site of the tumor as well as the type and the number of feeding arteries.