The neutrophil-to-lymphocyte ratio (NLR) has recently been reported to predict the prognosis of hepatocellular carcinoma (HCC). We explored whether NLR predicted the survival of patients with HCC undergoing transarterial chemoembolization (TACE), and developed a predictive model. In total, 1697 patients with HCC undergoing TACE as first-line therapy at two university hospitals were enrolled (derivation set n = 921, internal validation set n = 395, external validation set n = 381). The tumor size, tumor number, AFP level, vascular invasion, Child-Pugh score, objective response after TACE, and NLR, selected as predictors of overall survival (OS) via multivariate Cox's regression model, were incorporated into a 14-point risk prediction model (SNAVCORN score). The time-dependent areas under the receiver-operating characteristic curves for OS at 1, 3, and 5 years predicted by the SNAVCORN score were 0.812, 0.734, and 0.700 in the derivation set. Patients were stratified into three risk groups by SNAVCORN score (low, 0-4; intermediate, 5-9; high, 10-14). Compared with the low-risk group, the intermediate-risk (HR 3.10, < 0.001) and high-risk (HR 7.37, < 0.001) groups exhibited significantly greater mortality. The prognostic performance of the SNAVCORN score including NLR in patients with HCC treated with TACE was remarkable, much better than those of the conventional scores. The SNAVCORN score will guide future HCC treatment decisions.