It is important to evaluate the likelihood of fatality in patients with acute primary pontine hemorrhage (PPH) in emergency departments. We aimed to evaluate the clinical symptoms and computed tomography findings of PPH to develop a simple grading scale for predicting the mortality of PPH. Records of 101 consecutive patients admitted to our hospital with acute PPH between June 1, 2006, and January 31, 2014, were retrospectively reviewed. Independent predictors of 30-day mortality were identified by univariate and multivariate logistic regression analyses. A simple and easy clinical score (PPH score) was developed from independent factors to predict mortality in acute PPH. The PPH score was compared with the established intracerebral hemorrhage (ICH) score, which served as the reference scoring system. Overall mortality rate 30days after onset was 58.4% (59 of 101). Factors independently associated with 30-day mortality were Glasgow Coma Scale (GCS) score of 6 or less (P=.0051), absence of pupillary light reflex (P=.0003), and blood glucose of 180mg/dL or greater (P=.0312). The PPH score was the sum of independent factors, which were assigned 1 point each. The area under the receiver operating characteristic curve for predicting 30-day mortality was .90 (95% confidence interval [CI], .84-.95) for PPH score and .86 (95% CI, .78-.93) for ICH score. GCS score of 6 or less, absence of pupillary light reflex, and plasma glucose of 10mmol/L or greater are independent mortality predictors of PPH. The PPH score is a simple and reliable clinical grading scale for predicting 30-day mortality.