The prognostic nutritional index (PNI) is one of the immune parameters calculated on the basis of the serum albumin and the total lymphocyte count. The aim of the present study was to investigate the prognostic significance of the PNI for short- and long-term outcomes after liver resection for patients with hepatocellular carcinoma (HCC). Data from 162 surgically treated patients with HCC (without any previous treatment) were retrospectively analyzed. The cutoff value of preoperative PNI was 45.0, which was calculated by a receiver operating characteristic curve for predicting the recurrence of HCC after liver resection. Patients were divided into low (n=86) and high (n=76) PNI groups. In short-term outcomes, patients in the low PNI group were more likely to experience postoperative complications compared with those in the high PNI group. The 5-year disease-free survival (DFS) rate in the low PNI group was significantly lower compared with that in the high PNI group (20.5% vs. 48.7%). In the multivariate analysis, a low PNI was an independent prognostic factor for DFS (HR, 1.65; 95% CI, 1.00-2.71). In conclusion, the preoperative PNI may be a prognostic factor for evaluating short- and long-term outcomes after liver resection in patients with HCC.