The liver is the second most commonly injured organ following blunt abdominal trauma. The stable patient with minimal physical findings with a history of blunt abdominal trauma presents a challenge for diagnosis of liver injury. This study was conducted to determine the usefulness of hepatic transaminases in predicting the presence of liver injury and its severity following blunt abdominal trauma. In this retrospective study, we included all patients who had sustained blunt abdominal injury and were treated at our institution between January 2008 and December 2010. The grading of the liver injury was verified using CT scans or surgical findings. One hundred and eighty-two patients with blunt abdominal trauma underwent the required blood tests and were included in the study. Using receiver operating characteristic (ROC) curve assessment, optimum alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH) and γ-glutamyl transpeptidase (GGT) thresholds were determined to be >57 U/l, 113 U/l, 595 U/l and 50 U/l. ALT >57 U/l (OR, 66.1; P<0.001) and AST >113 U/l (OR, 30.6; P<0.001) were strongly associated with the presence of liver injuries. This association was also observed in patients with elevated LDH >595 U/l (OR, 3.8; P<0.001) and GGT >50 U/l (OR, 3.0; P<0.05). None of the laboratory tests were related to the severity of the liver injuries. In patients with blunt abdominal trauma, abnormal hepatic transaminase levels are associated with liver injuries. Patients with ALT >57 U/l and AST >113 U/l are strongly associated with liver injury and require further imaging studies and close management.