Treatment for hepatocellular carcinoma (HCC) with advanced cirrhosis, especially with hypersplenic thrombocytopenia, will be very difficult. Then we evaluated usefulness of concomitant splenectomy with treatment for patients with HCC, severe cirrhosis and huge splenomegaly. The preoperative mean platelet (Plt) count was 4.6 × 10(4)/µL and the mean longest diameter of spleen on CT was 143.0 mm. The mean Plt count on postoperative days 14 and 28 was 23.1 × 10(4)/µL (p=0.005) and 16.1 × 10(4)/µL (p=0.01), respectively and improved significantly compared with preoperative one. A white blood cell count and serum albumin also improved significantly on postoperative days 14 and 28, respectively. Treatment for recurrent HCC after splenectomy was preformed 2.4 times per patient (transarterial chemoembolization 13 times and radiofrequency ablation 4 times/7 patients). Now 5 patients are alive and the mean survival period was 17.3 months (range 8-38 months). It maybe said that concomitant splenectomy for cirrhotic patients with HCC and huge splenomegaly who need to receive a treatment for HCC was useful in our study, because those patients could receive a treatment for recurrent HCC repeatedly, and that probably contributes to the improvement of prognosis.