Burn injuries impose a considerable burden on healthcare systems in Iran. It is among the top ten causes of mortality and a main cause of disability.This study aimed to examine factors influencing mortality in burn patients admitted to the main educational tertiary referral hospital in Kermanshah.All patients admitted to the Imam Khomeini Hospital (from March 2011 to March 2012), due to thermal burn injuries were included in the study. We applied multiple logistic regressions to identify risk and protective factors of mortality. Also we calculated lethal area fifty percent (LA50), as an aggregate index for hospital quality.During the study period, 540 burn patients were admitted. Male to female ratio was 1.12:1. Twenty three percent of the patients were less than 15 years-old. Median of age was 25 years (Inter Quartile Range, 16 - 37). Overall, probability of death was 25.8%. Lethal area fifty percent (LA50) was 50.82 (CI 95%: 47.76 - 54.48). In the final model, after adjustment of sex, age, total body surface area (TBSA), cause of burn and it's severity, female gender (P < 0.05), age ≥ 60 years (in comparison with age less than 15 years, P < 0.05) and larger burn size (P < 0.0001) were identified as the main risk factors of death in these patients.Findings showed that the main risk factors of death were female gender, burn size and old age. Directing more attention to these vulnerable patients is required to reduce mortality and improve patient survival.